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rfc:rfc2801

Network Working Group D. Burdett Request for Comments: 2801 Commerce One Category: Informational April 2000

               Internet Open Trading Protocol - IOTP
                            Version 1.0

Status of this Memo

 This memo provides information for the Internet community.  It does
 not specify an Internet standard of any kind.  Distribution of this
 memo is unlimited.

Copyright Notice

 Copyright (C) The Internet Society (2000).  All Rights Reserved.

Abstract

 The Internet Open Trading Protocol (IOTP) provides an interoperable
 framework for Internet commerce. It is payment system independent and
 encapsulates payment systems such as SET, Secure Channel
 Credit/Debit, Mondex, CyberCoin, GeldKarte, etc. IOTP is able to
 handle cases where such merchant roles as the shopping site, the
 Payment Handler, the Delivery Handler of goods or services, and the
 provider of customer support are performed by different parties or by
 one party.

Table of Contents

 1.  Background .....................................................7
   1.1  Commerce on the Internet, a Different Model .................7
   1.2  Benefits of IOTP ............................................9
   1.3  Baseline IOTP ..............................................10
   1.4  Objectives of Document .....................................10
   1.5  Scope of Document ..........................................11
   1.6  Document Structure .........................................11
   1.7  Intended Readership ........................................13
       1.7.1  Reading Guidelines ...................................13
 2.  Introduction ..................................................14
   2.1  Trading Roles ..............................................16
   2.2  Trading Exchanges ..........................................18
       2.2.1  Offer Exchange .......................................19
       2.2.2  Payment Exchange .....................................21
       2.2.3  Delivery Exchange ....................................24
       2.2.4  Authentication Exchange ..............................26
   2.3  Scope of Baseline IOTP .....................................28

Burdett Informational [Page 1] RFC 2801 IOTP/1.0 April 2000

 3.  Protocol Structure ............................................31
   3.1  Overview ...................................................32
       3.1.1  IOTP Message Structure ...............................32
       3.1.2  IOTP Transactions ....................................34
   3.2  IOTP Message ...............................................35
       3.2.1  XML Document Prolog ..................................37
   3.3  Transaction Reference Block ................................37
       3.3.1  Transaction Id Component .............................38
       3.3.2  Message Id Component .................................39
       3.3.3  Related To Component .................................41
   3.4  ID Attributes ..............................................42
       3.4.1  IOTP Message ID Attribute Definition .................43
       3.4.2  Block and Component ID Attribute Definitions .........44
       3.4.3  Example of use of ID Attributes ......................46
   3.5  Element References .........................................46
   3.6  Extending IOTP .............................................48
       3.6.1  Extra XML Elements ...................................49
       3.6.2  Opaque Embedded Data .................................50
   3.7  Packaged Content Element ...................................50
       3.7.1  Packaging HTML .......................................52
       3.7.2  Packaging XML ........................................53
   3.8  Identifying Languages ......................................54
   3.9  Secure and Insecure Net Locations ..........................54
   3.10 Cancelled Transactions .....................................55
       3.10.1 Cancelling Transactions ..............................55
       3.10.2 Handling Cancelled Transactions ......................56
 4.  IOTP Error Handling ...........................................56
   4.1  Technical Errors ...........................................57
   4.2  Business Errors ............................................57
   4.3  Error Depth ................................................58
       4.3.1  Transport Level ......................................58
       4.3.2  Message Level ........................................58
       4.3.3  Block Level ..........................................59
   4.4  Idempotency, Processing Sequence, and Message Flow .........61
   4.5  Server Role Processing Sequence ............................62
       4.5.1  Initiating Transactions ..............................62
       4.5.2  Processing Input Messages ............................63
       4.5.3  Cancelling a Transaction .............................70
       4.5.4  Retransmitting Messages ..............................70
   4.6  Client Role Processing Sequence ............................71
       4.6.1  Initiating Transactions ..............................71
       4.6.2  Processing Input Messages ............................72
       4.6.3  Cancelling a Transaction .............................74
       4.6.4  Retransmitting Messages ..............................74
 5.  Security Considerations .......................................74
   5.1  Determining whether to use digital signatures ..............74
   5.2  Symmetric and Asymmetric Cryptography ......................76
   5.3  Data Privacy ...............................................77

Burdett Informational [Page 2] RFC 2801 IOTP/1.0 April 2000

   5.4  Payment Protocol Security ..................................77
 6.  Digital Signatures and IOTP ...................................77
   6.1  How IOTP uses Digital Signatures ...........................77
       6.1.1  IOTP Signature Example ...............................80
       6.1.2  OriginatorInfo and RecipientInfo Elements ............82
       6.1.3  Using signatures to Prove Actions Complete
              Successfully .........................................83
   6.2  Checking a Signature is Correctly Calculated ...............84
   6.3  Checking a Payment or Delivery can occur ...................85
       6.3.1  Check Request Block sent Correct Organisation ........86
       6.3.2  Check Correct Components present in Request Block ....91
       6.3.3  Check an Action is Authorised ........................91
 7.  Trading Components ............................................93
   7.1  Protocol Options Component .................................96
   7.2  Authentication Request Component ...........................97
   7.3  Authentication Response Component ..........................98
   7.4  Trading Role Information Request Component .................99
   7.5  Order Component ...........................................100
       7.5.1  Order Description Content ...........................101
       7.5.2  OkFrom and OkTo Timestamps ..........................101
   7.6  Organisation Component ....................................102
       7.6.1  Organisation IDs ....................................104
       7.6.2  Trading Role Element ................................105
       7.6.3  Contact Information Element .........................108
       7.6.4  Person Name Element .................................109
       7.6.5  Postal Address Element ..............................110
   7.7  Brand List Component ......................................111
       7.7.1  Brand Element .......................................113
       7.7.2  Protocol Brand Element ..............................115
       7.7.3  Protocol Amount Element .............................116
       7.7.4  Currency Amount Element .............................117
       7.7.5  Pay Protocol Element ................................118
   7.8  Brand Selection Component .................................120
       7.8.1  Brand Selection Brand Info Element ..................122
       7.8.2  Brand Selection Protocol Amount Info Element ........122
       7.8.3  Brand Selection Currency Amount Info Element ........123
   7.9  Payment Component .........................................123
   7.10 Payment Scheme Component ..................................125
   7.11 Payment Receipt Component .................................126
   7.12 Payment Note Component ....................................128
   7.13 Delivery Component ........................................129
       7.13.1 Delivery Data Element ...............................130
   7.14 Consumer Delivery Data Component ..........................132
   7.15 Delivery Note Component ...................................133
   7.16 Status Component ..........................................134
       7.16.1 Offer Completion Codes ..............................137
       7.16.2 Payment Completion Codes ............................138
       7.16.3 Delivery Completion Codes ...........................140

Burdett Informational [Page 3] RFC 2801 IOTP/1.0 April 2000

       7.16.4 Authentication Completion Codes .....................142
       7.16.5 Undefined Completion Codes ..........................144
       7.16.6 Transaction Inquiry Completion Codes ................144
   7.17 Trading Role Data Component ...............................144
       7.17.1 Who Receives a Trading Role Data Component ..........145
   7.18 Inquiry Type Component ....................................146
   7.19 Signature Component .......................................147
       7.19.1 IOTP usage of signature elements and attributes .....148
       7.19.2 Offer Response Signature Component ..................150
       7.19.3 Payment Receipt Signature Component .................151
       7.19.4 Delivery Response Signature Component ...............152
       7.19.5 Authentication Request Signature Component ..........152
       7.19.6 Authentication Response Signature Component .........153
       7.19.7 Inquiry Request Signature Component .................153
       7.19.8 Inquiry Response Signature Component ................153
       7.19.9 Ping Request Signature Component ....................153
       7.19.10 Ping Response Signature Component...................154
   7.20 Certificate Component .....................................154
       7.20.1 IOTP usage of signature elements and attributes .....154
   7.21 Error Component ...........................................154
       7.21.1 Error Processing Guidelines .........................157
       7.21.2 Error Codes .........................................158
       7.21.3 Error Location Element ..............................162
 8.  Trading Blocks ...............................................163
   8.1  Trading Protocol Options Block ............................166
   8.2  TPO Selection Block .......................................167
   8.3  Offer Response Block ......................................168
   8.4  Authentication Request Block ..............................169
   8.5  Authentication Response Block .............................170
   8.6  Authentication Status Block ...............................171
   8.7  Payment Request Block .....................................171
   8.8  Payment Exchange Block ....................................173
   8.9  Payment Response Block ....................................173
   8.10 Delivery Request Block ....................................175
   8.11 Delivery Response Block ...................................176
   8.12 Inquiry Request Trading Block .............................177
   8.13 Inquiry Response Trading Block ............................177
   8.14 Ping Request Block ........................................179
   8.15 Ping Response Block .......................................179
   8.16 Signature Block ...........................................181
       8.16.1 Signature Block with Offer Response .................182
       8.16.2 Signature Block with Payment Request ................182
       8.16.3 Signature Block with Payment Response ...............182
       8.16.4 Signature Block with Delivery Request ...............182
       8.16.5 Signature Block with Delivery Response ..............182
   8.17 Error Block ...............................................183
   8.18 Cancel Block ..............................................184
 9.  Internet Open Trading Protocol Transactions ..................184

Burdett Informational [Page 4] RFC 2801 IOTP/1.0 April 2000

   9.1  Authentication and Payment Related IOTP Transactions ......185
       9.1.1  Authentication Document Exchange ....................188
       9.1.2  Offer Document Exchange .............................194
       9.1.3  Payment Document Exchange ...........................203
       9.1.4  Delivery Document Exchange ..........................209
       9.1.5  Payment and Delivery Document Exchange ..............212
       9.1.6  Baseline Authentication IOTP Transaction ............216
       9.1.7  Baseline Deposit IOTP Transaction ...................218
       9.1.8  Baseline Purchase IOTP Transaction ..................220
       9.1.9  Baseline Refund IOTP Transaction ....................222
       9.1.10 Baseline Withdrawal IOTP Transaction ................224
       9.1.11 Baseline Value Exchange IOTP Transaction ............226
       9.1.12 Valid Combinations of Document Exchanges ............230
       9.1.13 Combining Authentication Transactions with other
              Transactions ........................................234
   9.2  Infrastructure Transactions ...............................235
       9.2.1  Baseline Transaction Status Inquiry IOTP Transaction 235
       9.2.2  Baseline Ping IOTP Transaction ......................241
 10. Retrieving Logos .............................................244
   10.1 Logo Size .................................................245
   10.2 Logo Color Depth ..........................................245
   10.3 Logo Net Location Examples ................................246
 11. Brands .......................................................246
   11.1 Brand Definitions and Brand Selection .....................246
       11.1.1 Definition of Payment Instrument ....................247
       11.1.2 Definition of Brand .................................247
       11.1.3 Definition of Dual Brand ............................248
       11.1.4 Definition of Promotional Brand .....................248
       11.1.5 Identifying Promotional Brands ......................249
   11.2 Brand List Examples .......................................251
       11.2.1 Simple Credit Card Based Example ....................252
       11.2.2 Credit Card Brand List Including Promotional Brands..253
       11.2.3 Brand Selection Example .............................254
       11.2.4 Complex Electronic Cash Based Brand List ............255
 12. IANA Considerations ..........................................257
   12.1 Codes Controlled by IANA ..................................257
   12.2 Codes not controlled by IANA ..............................263
 13. Internet Open Trading Protocol Data Type Definition ..........263
 14. Glossary .....................................................277
 15. References ...................................................284
 16. Author's Address .............................................287
 17. Full Copyright Statement .....................................290

Burdett Informational [Page 5] RFC 2801 IOTP/1.0 April 2000

Table of Figures

 Figure 1 IOTP Trading Roles                                       16
 Figure 2 Offer Exchange                                           19
 Figure 3 Payment Exchange                                         22
 Figure 4 Delivery Exchange                                        25
 Figure 5 Authentication Exchange                                  27
 Figure 6 IOTP Message Structure                                   33
 Figure 7 An IOTP Transaction                                      34
 Figure 8 Example use of ID attributes                             46
 Figure 9 Element References                                       48
 Figure 10 Signature Digests                                       79
 Figure 11 Example use of Signatures for Baseline Purchase         81
 Figure 12 Checking a Payment Handler can carry out a Payment      87
 Figure 13 Checking a Delivery Handler can carry out a Delivery    90
 Figure 14 Trading Components                                      94
 Figure 15 Brand List Element Relationships                       113
 Figure 16 Trading Blocks                                         164
 Figure 17 Payment and Authentication Message Flow Combinations   187
 Figure 18 Authentication Document Exchange                       190
 Figure 19 Brand Dependent Offer Document Exchange                196
 Figure 20 Brand Independent Offer Exchange                       198
 Figure 21 Payment Document Exchange                              204
 Figure 22 Delivery Document Exchange                             210
 Figure 23 Payment and Delivery Document Exchange                 214
 Figure 24 Baseline Authentication IOTP Transaction               217
 Figure 25 Baseline Deposit IOTP Transaction                      219
 Figure 26 Baseline Purchase IOTP Transaction                     221
 Figure 27 Baseline Refund IOTP Transaction                       223
 Figure 28 Baseline Withdrawal IOTP Transaction                   225
 Figure 29 Baseline Value Exchange IOTP Transaction               228
 Figure 30 Baseline Value Exchange Signatures                     230
 Figure 31 Valid Combinations of Document Exchanges               231
 Figure 32 Baseline Transaction Status Inquiry                    238
 Figure 33 Baseline Ping Messages                                 242

Burdett Informational [Page 6] RFC 2801 IOTP/1.0 April 2000

1. Background

 The Internet Open Trading Protocol (IOTP) provides an interoperable
 framework for Internet commerce. It is payment system independent and
 encapsulates payment systems such as SET, Mondex, CyberCash,
 DigiCash, GeldKarte, etc. IOTP is able to handle cases where such
 merchant roles as the shopping site, the Payment Handler, the
 Delivery Handler of goods or services, and the provider of customer
 support are performed by different parties or by one party.
 The developers of IOTP seek to provide a virtual capability that
 safely replicates the real world, the paper based, traditional,
 understood, accepted methods of trading, buying, selling, value
 exchanging that has existed for many hundreds of years.  The
 negotiation of who will be the parties to the trade, how it will be
 conducted, the presentment of an offer, the method of payment, the
 provision of a payment receipt, the delivery of goods and the receipt
 of goods. These are events that are taken for granted in the course
 of real world trade. IOTP has been produced to provide the same for
 the virtual world, and to prepare and provide for the introduction of
 new models of trading made possible by the expanding presence of the
 virtual world.
 The other fundamental ideal of the IOTP effort is to produce a
 definition of these trading events in such a way that no matter where
 produced, two unfamiliar parties using electronic commerce
 capabilities to buy and sell that conform to the IOTP specifications
 will be able to complete the business safely and successfully.
 In summary, IOTP supports:
 o Familiar trading models
 o New trading models
 o Global interoperability
 The remainder of this section provides background to why IOTP was
 developed. The specification itself starts in the next chapter.

1.1 Commerce on the Internet, a Different Model

 The growth of the Internet and the advent of electronic commerce are
 bringing about enormous changes around the world in society, politics
 and government, and in business. The ways in which trading partners
 communicate, conduct commerce, are governed have been enriched and
 changed forever.

Burdett Informational [Page 7] RFC 2801 IOTP/1.0 April 2000

 One of the very fundamental changes about which IOTP is concerned is
 taking place in the way consumers and merchants trade.
 Characteristics of trading that have changed markedly include:
 o  Presence: Face-to-face transactions become the exception, not the
    rule.  Already with the rise of mail order and telephone order
    placement this change has been felt in western commerce.
    Electronic commerce over the Internet will further expand the
    scope and volume of transactions conducted without ever seeing the
    people who are a part of the enterprise with whom one does
    business.
 o  Authentication: An important part of personal presence is the
    ability of the parties to use familiar objects and dialogue to
    confirm they are who they claim to be. The seller displays one or
    several well known financial logos that declaim his ability to
    accept widely used credit and debit instruments in the payment
    part of a purchase. The buyer brings government or financial
    institution identification that assures the seller she will be
    paid. People use intangibles such as personal appearance and
    conduct, location of the store, apparent quality and familiarity
    with brands of merchandise, and a good clear look in the eye to
    reinforce formal means of authentication.
 o  Payment Instruments: Despite the enormous size of bank card
    financial payments associations and their members, most of the
    world's trade still takes place using the coin of the realm or
    barter. The present infrastructure of the payments business cannot
    economically support low value transactions and could not survive
    under the consequent volumes of transactions if it did accept low
    value transactions.
 o  Transaction Values: New meaning for low value transactions arises
    in the Internet where sellers may wish to offer for example, pages
    of information for fractions of currency that do not exist in the
    real world.
 o  Delivery: New modes of delivery must be accommodated such as
    direct electronic delivery. The means by which receipt is
    confirmed and the execution of payment change dramatically where
    the goods or services have extremely low delivery cost but may in
    fact have very high value.  Or, maybe the value is not high, but
    once delivery occurs the value is irretrievably delivered so
    payment must be final and non-refundable but delivery nonetheless
    must still be confirmed before payment.  Incremental delivery such
    as listening or viewing time or playing time are other models that
    operate somewhat differently in the virtual world.

Burdett Informational [Page 8] RFC 2801 IOTP/1.0 April 2000

1.2 Benefits of IOTP

 ELECTRONIC COMMERCE SOFTWARE VENDORS
 Electronic Commerce Software Vendors will be able to develop e-
 commerce products which are more attractive as they will inter-
 operate with any other vendors' software. However, since IOTP focuses
 on how these solutions communicate, there is still plenty of
 opportunity for product differentiation.
 PAYMENT BRANDS
 IOTP provides a standard framework for encapsulating payment
 protocols.  This means that it is easier for payment products to be
 incorporated into IOTP solutions. As a result the payment brands will
 be more widely distributed and available on a wider variety of
 platforms.
 MERCHANTS
 There are several benefits for Merchants:
 o  they will be able to offer a wider variety of payment brands,
 o  they can be more certain that the customer will have the software
    needed to complete the purchase
 o  through receiving payment and delivery receipts from their
    customers, they will be able to provide customer care knowing that
    they are dealing with the individual or organisation with which
    they originally traded
 o  new merchants will be able to enter this new (Internet) market-
    place with new products and services, using the new trading
    opportunities which IOTP presents
 BANKS AND FINANCIAL INSTITUTIONS
 There are also several benefits for Banks and Financial Institutions:
 o  they will be able to provide IOTP support for merchants
 o  they will find new opportunities for IOTP related services:
  1. providing customer care for merchants
  2. fees from processing new payments and deposits

Burdett Informational [Page 9] RFC 2801 IOTP/1.0 April 2000

 o  they have an opportunity to build relationships with new types of
    merchants
 CUSTOMERS
 For Customers there are several benefits:
 o  they will have a larger selection of merchants with whom they can
    trade
 o  there is a more consistent interface when making the purchase
 o  there are ways in which they can get their problems fixed through
    the merchant (rather than the bank!)
 o  there is a record of their transaction which can be used, for
    example, to feed into accounting systems or, potentially, to
    present to the tax authorities

1.3 Baseline IOTP

 This specification is Baseline IOTP. It is a Baseline in that it
 contains ways of doing trades on the Internet which are the most
 common, for example purchases and refunds.
 The group that has worked on the IOTP see an extended version being
 developed over time but feel a need to focus on a limited function
 but completely usable specification in order that implementers can
 develop solutions that work now.
 During this period it is anticipated that there will be no changes to
 the scope of this specification with the only changes made being
 limited to corrections where problems are found. Software solutions
 have been developed based on earlier versions of this specification
 (for example version 0.9 published in early 1998 and earlier
 revisions of version 1.0 published during 1999) which prove that the
 IOTP works.

1.4 Objectives of Document

 The objectives of this document are to provide a specification of
 version 1.0 of the Internet Open Trading Protocols which can be used
 to design and implement systems which support electronic trading on
 the Internet using the Internet Open Trading Protocols.

Burdett Informational [Page 10] RFC 2801 IOTP/1.0 April 2000

 The purpose of the document is:
 o  to allow potential developers of products based on the protocol to
    develop software/hardware solutions which use the protocol
 o  to allow the financial services industry to understand a
    developing electronic commerce trading protocol that encapsulates
    (without modification) any of the current or developing payment
    schemes now being used or considered by their merchant customer
    base

1.5 Scope of Document

 The protocol describes the content, format and sequences of messages
 that pass among the participants in an electronic trade - consumers,
 merchants and banks or other financial institutions, and customer
 care providers.  These are required to support the electronic
 commerce transactions outlined in the objectives above.
 The protocol is designed to be applicable to any electronic payment
 scheme since it targets the complete purchase process where the
 movement of electronic value from the payer to the payee is only one,
 but important, step of many that may be involved to complete the
 trade.
 Payment Scheme which IOTP could support include MasterCard Credit,
 Visa Credit, Mondex Cash, Visa Cash, GeldKarte, eCash, CyberCoin,
 Millicent, Proton, etc.
 Each payment scheme contains some message flows which are specific to
 that scheme. These scheme-specific parts of the protocol are
 contained in a set of payment scheme supplements to this
 specification.
 The document does not prescribe the software and processes that will
 need to be implemented by each participant. It does describe the
 framework necessary for trading to take place.
 This document also does not address any legal or regulatory issues
 surrounding the implementation of the protocol or the information
 systems which use them.

1.6 Document Structure

 The document consists of the following sections:
 o  Section 1 - Background: This section gives a brief background on
    electronic commerce and the benefits IOTP offers.

Burdett Informational [Page 11] RFC 2801 IOTP/1.0 April 2000

 o  Section 2 - Introduction: This section describes the various
    Trading Exchanges and shows how these trading exchanges are used
    to construct the IOTP Transactions. This section also explains
    various Trading Roles that would participate in electronic trade.
 o  Section 3 - Protocol Structure: This section summarises how
    various IOTP transactions are constructed using the Trading Blocks
    and Trading Components that are the fundamental building blocks
    for IOTP transactions. All IOTP transaction messages are well
    formed XML documents.
 o  Section 4 - IOTP Error Handling: This section describes how to
    process exceptions and errors during the protocol message exchange
    and trading exchange processing. This section provides a generic
    overview of the exception handling. This section should be read
    carefully.
 o  Section 5 - Security Considerations: This section considers from
    an IETF perspective, how IOTP addresses security. It includes: how
    to determine whether to use digital signatures with IOTP, how IOTP
    address data privacy, and how security built into payment
    protocols relate to IOTP security.
 o  Section 6 - Digital Signatures and IOTP: This section provides an
    overview of how IOTP uses digital signatures; how to check a
    signature is correctly calculated and how the various Trading
    Roles that participate in trade should check signatures when
    required.
 o  Section 7 - Trading Components: This section defines the XML
    elements required by Trading Components.
 o  Section 8 - Trading Blocks: This section describes how Trading
    Blocks are constructed from Trading Components.
 o  Section 9 - Internet Open Trading Protocol Transactions: This
    section describes all the IOTP Baseline transactions. It refers to
    Trading Blocks and Trading Components and Signatures. This section
    doesn't directly link error handling during the protocol
    exchanges, the reader is advised to understand Error Handling as
    defined in section before reading this section.
 o  Section 10 - Retrieving Logos: This section describes how IOTP
    specific logos can be retrieved.

Burdett Informational [Page 12] RFC 2801 IOTP/1.0 April 2000

 o  Section 11 - Brands: This section provides: an overview of Brand
    Definitions and Brand Selection which describe how a Consumer can
    select a Brand from a list provided by the Merchant; as well as
    some examples of Brand Lists.
 o  Section 12 - IANA Considerations: This section describes how new
    values for codes used by IOTP are co-ordinated.
 o  Section 13 - Internet Open Trading Protocol Data Type Definition:
    This section contains the XML Data Type Definitions for IOTP.
 o  Section 14 - Glossary. This describes all the major terminology
    used by IOTP.
 o  Section 15 - A list of the other documents referenced by the IOTP
    specification.
 o  Section 16 - The Author's Address
 o  Section 17 - Full Copyright Statement

1.7 Intended Readership

 Software and hardware developers; development analysts; business and
 technical planners; industry analysts; merchants; bank and other
 payment handlers; owners, custodians, and users of payment protocols.

1.7.1 Reading Guidelines

 This IOTP specification is structured primarily in a sequence
 targeted at people who want to understand the principles of IOTP.
 However from practical implementation experience by implementers of
 earlier of versions of the protocol new readers who plan to implement
 IOTP may prefer to read the document in a different sequence as
 described below.
 Review the transport independent parts of the specification. This
 covers:
 o Section 14 - Glossary
 o Section 1 - Background
 o Section 2 - Introduction
 o Section 3 - Protocol Structure
 o Section 4 - IOTP Error Handling

Burdett Informational [Page 13] RFC 2801 IOTP/1.0 April 2000

 o Section 5 - Security Considerations
 o Section 9 - Internet Open Trading Protocol Transactions
 o Section 11 - Brands
 o Section 12 - IANA Considerations
 o Section 10 - Retrieving Logos
 Review the detailed XML definitions:
 o Section 8 - Trading Blocks
 o Section 7 - Trading Components
 o Section 6 - Digital Signatures and IOTP

2. Introduction

 The Internet Open Trading Protocols (IOTP) define a number of
 different types of IOTP Transactions:
 o  Purchase. This supports a purchase involving an offer, a payment
    and optionally a delivery
 o  Refund. This supports the refund of a payment as a result of,
    typically, an earlier purchase
 o  Value Exchange. This involves two payments which result in the
    exchange of value from one combination of currency and payment
    method to another
 o  Authentication. This supports one organisation or individual to
    check that another organisation or individual are who they appear
    to be.
 o  Withdrawal. This supports the withdrawal of electronic cash from a
    financial institution
 o  Deposit. This supports the deposit of electronic cash at a
    financial institution
 o  Inquiry. This supports inquiries on the status of an IOTP
    transaction which is either in progress or is complete

Burdett Informational [Page 14] RFC 2801 IOTP/1.0 April 2000

 o  Ping. This supports a simple query which enables one IOTP aware
    application to determine whether another IOTP application running
    elsewhere is working or not.
 These IOTP Transactions are "Baseline" transactions since they have
 been identified as a minimum useful set of transactions. Later
 versions of IOTP may include additional types of transactions.
 Each of the IOTP Transactions above involve:
 o  a number of organisations playing a Trading Role, and
 o  a set of Trading Exchanges. Each Trading Exchange involves the
    exchange of data, between Trading Roles, in the form of a set of
    Trading Components.
 Trading Roles, Trading Exchanges and Trading Components are described
 below.

Burdett Informational [Page 15] RFC 2801 IOTP/1.0 April 2000

2.1 Trading Roles

 The Trading Roles identify the different parts which organisations
 can take in a trade. The five Trading Roles used within IOTP are
 illustrated in the diagram below.
  • +*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*
            Merchant Customer Care Provider resolves   ----------
       ---------------------------------------------->| Merchant |
      |          Consumer disputes and problems       |Cust.Care.|
      |                                               | Provider |
      |                                                ----------
      |
                 Payment Handler accepts or makes     ----------
      |    ------------------------------------------>| Payment  |
      |   |             Payment for Merchant          | Handler  |
      |   |                                            ----------
      v   v
  ----------    Consumer makes purchases or obtains    ----------
 | Consumer |<--------------------------------------->| Merchant |
  ----------             refund from Merchant          ----------
      ^
      |         Delivery Handler supplies goods or     ----------
      |---------------------------------------------->|Deliverer |
                     services for Merchant            | Handler  |
                                                       ----------
  • -*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*
                  Figure 1 IOTP Trading Roles

Burdett Informational [Page 16] RFC 2801 IOTP/1.0 April 2000

 The roles are:
 o  Consumer. The person or organisation which is to receive and pay
    for the goods or services
 o  Merchant. The person or organisation from whom the purchase is
    being made and who is legally responsible for providing the goods
    or services and receives the benefit of the payment made
 o  Payment Handler. The entity that physically receives the payment
    from the Consumer on behalf of the Merchant
 o  Delivery Handler. The entity that physically delivers the goods or
    services to the Consumer on behalf of the Merchant.
 o  Merchant Customer Care Provider. The entity that is involved with
    customer dispute negotiation and resolution on behalf of the
    Merchant
 Roles may be carried out by the same organisation or different
 organisations. For example:
 o  in the simplest case one physical organisation (e.g., a merchant)
    could handle the purchase, accept the payment, deliver the goods
    and provide merchant customer care
 o  at the other extreme, a merchant could handle the purchase but
    instruct the consumer to pay a bank or financial institution,
    request that delivery be made by an overnight courier firm and to
    contact an organisation which provides 24x7 service if problems
    arise.
 Note that in this specification, unless stated to the contrary, when
 the words Consumer, Merchant, Payment Handler, Delivery Handler or
 Customer Care Provider are used, they refer to the Trading Role
 rather than an actual organisation.
 An individual organisation may take multiple roles. For example a
 company which is selling goods and services on the Internet could
 take the role of Merchant when selling goods or services and the role
 of Consumer when the company is buying goods or services itself.
 As roles occur in different places there is a need for the
 organisations involved in the trade to exchange data, i.e. to carry
 out Trading Exchanges, so that the trade can be completed.

Burdett Informational [Page 17] RFC 2801 IOTP/1.0 April 2000

2.2 Trading Exchanges

 The Internet Open Trading Protocols identify four Trading Exchanges
 which involve the exchange of data between the Trading Roles. The
 Trading Exchanges are:
 o  Offer. The Offer Exchange results in the Merchant providing the
    Consumer with the reason why the trade is taking place. It is
    called an Offer since the Consumer must accept the Offer if a
    trade is to continue
 o  Payment. The Payment Exchange results in a payment of some kind
    between the Consumer and the Payment Handler. This may occur in
    either direction
 o  Delivery. The Delivery Exchange transmits either the on-line
    goods, or delivery information about physical goods from the
    Delivery Handler to the Consumer, and
 o  Authentication. The Authentication Exchange can be used by any
    Trading Role to authenticate another Trading Role to check that
    they are who they appear to be.
 IOTP Transactions are composed of various combinations of these
 Trading Exchanges.  For example, an IOTP Purchase transaction
 includes Offer, Payment, and Delivery Trading Exchanges.  As another
 example, an IOTP Value Exchange transaction is composed of an Offer
 Trading Exchange and two Payment Trading Exchanges.
 Trading Exchanges consist of Trading Components that are transmitted
 between the various Trading Roles.  Where possible, the number of
 round-trip delays in an IOTP Transaction is minimised by packing the
 Components from several Trading Exchanges into combination IOTP
 Messages.  For example, the IOTP Purchase transaction combines a
 Delivery Organisation Component with an Offer Response Component in
 order to avoid an extra Consumer request and response.
 Each of the IOTP Trading Exchanges is described in more detail below.
 For clarity of description, these describe the Trading Exchanges as
 though they were standalone operations.  For performance reasons, the
 Trading Exchanges are intermingled in the actual IOTP Transaction
 definitions.

Burdett Informational [Page 18] RFC 2801 IOTP/1.0 April 2000

2.2.1 Offer Exchange

 The goal of the Offer Exchange is for the Merchant to provide the
 Consumer with information about the trade so that the Consumer can
 decide whether to continue with the trade. This is illustrated in the
 figure below.

*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*

 Consumer
   |  Merchant

STEP | | 1. Consumer decides to trade and sends information about the

           transaction (requests an offer) to the Merchant e.g.,
           using HTML.
   C --> M Data: Information on what is being purchased (Offer Request)
           - outside scope of IOTP

2. Merchant checks the information provided by the Consumer,

           creates an Offer optionally signs it and sends it to the
           Consumer.
   C <-- M OFFER RESPONSE. Components: Status; Organisation(s)
           (Consumer, DelivTo, Merchant, Payment Handler, Customer
           Care); Order; Payment; Delivery; TradingRoleData (optional)
           Offer Response Signature (optional) that signs other
           components

3. Consumer checks the information from the Merchant and

           decides whether to continue.

*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*

                         Figure 2 Offer Exchange
 An Offer Exchange uses the following Trading Components that are
 passed between the Consumer and the Merchant:
 o  the Status component is used to indicate to other parties that a
    valid Offer Response has been generated
 o  the Organisation Component contains information which describes
    the Organisations which are taking a role in the trade:
  1. the consumer provides information, about who the consumer is

and, if goods or services are being delivered, where the goods

       or services are to be delivered to

Burdett Informational [Page 19] RFC 2801 IOTP/1.0 April 2000

  1. the merchant augments this information by providing information

about the merchant, the Payment Handler, the customer care

       provider and, if goods or services are being delivered, the
       Delivery Handler
 o  the Order Component contains descriptions of the goods or services
    which will result from the trade if the consumer agrees to the
    offer.  This information is sent by the Merchant to the consumer
    who should verify it
 o  the Payment Component generated by the Merchant, contains details
    of how much to pay, the currency and the payment direction, for
    example the consumer could be asking for a refund. Note that there
    may be more than one payment in a trade
 o  the Delivery Component, also generated by the Merchant, is used if
    goods or services are being delivered. This contains information
    about how delivery will occur, for example by post or using e-mail
 o  the Trading Role Data component contains data the Merchant wants
    to forward to another Trading Role such as a Payment Handler or
    Delivery Handler
 o  the "Offer Response" Signature Component, if present, digitally
    signs all of the above components to ensure their integrity.
 The exact content of the information provided by the Merchant to the
 Consumer will vary depending on the type of IOTP Transaction. For
 example:
 o  low value purchases may not need a signature
 o  the amount to be paid may vary depending on the payment brand and
    payment protocol used
 o  some offers may not involve the delivery of any goods
 o  a value exchange will involve two payments
 o  a merchant may not offer customer care.
 Information provided by the consumer to the merchant is provided
 using a variety of methods, for example, it could be provided:
 o  using [HTML] pages as part of the "shopping experience" of the
    consumer.

Burdett Informational [Page 20] RFC 2801 IOTP/1.0 April 2000

 o  Using the Open Profiling Standard [OPS] which has recently been
    proposed,
 o  in the form of Organisation Components associated with an
    authentication of a Consumer by a Merchant
 o  as Order Components in a later version of IOTP.

2.2.2 Payment Exchange

 The goal of the Payment Exchange is for a payment to be made from the
 Consumer to a Payment Handler or vice versa using a payment brand and
 payment protocol selected by the Consumer. A secondary goal is to
 optionally provide the Consumer with a digitally signed Payment
 Receipt which can be used to link the payment to the reason for the
 payment as described in the Offer Exchange.
 Payment Exchanges can work in a variety of ways. The most general
 case where the trade is dependent on the payment brand and protocol
 used is illustrated in the diagram below. Simpler payment exchanges
 are possible.

*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*

Consumer  Pay Handler
   |  Merchant |

STEP | | | 1. Consumer decides to trade and sends information

                  about the transaction (requests an offer) to the
                  Merchant e.g., using HTML.
   C --> M        Information on what is being paid for (outside
                  scope of IOTP

2. Merchant decides which payment brand, payment

                  protocols and currencies/amounts to offer,
                  places then in a Brand List Component and sends
                  them to the Consumer
   C <-- M        Components: Brand List

3. Consumer selects the payment brand, protocol and

                  currency/amount to use, creates a Brand Selection
                  component and sends it to the Merchant
   C --> M        Component: Brand List Selection

Burdett Informational [Page 21] RFC 2801 IOTP/1.0 April 2000

4. Merchant checks Brand Selection, creates a Payment

                  Amount information, optionally signs it to
                  authorise payment and sends it to the Consumer
   C <-- M        Component: Payment; Organisation(s) (Merchant and
                  Payment Handler); Optional Offer Response Signature
                  that signs other components

5. Consumer checks the Payment Amount information and

                  if OK requests that the payment starts by sending
                  information to the Payment Handler
   C --------> P  PAYMENT REQUEST. Components: Status, Payment;
                  Organisations (Merchant and Payment Handler);
                  Trading Role Data (optional); Optional Offer
                  Response Signature that signs other components;
                  Pay Scheme Data

6. Payment Handler checks information including

                  optional signature and if OK starts exchanging Pay
                  Scheme Data components for selected payment brand
                  and payment protocol
   C <-------> P  PAYMENT EXCHANGE. Component: Pay Scheme Data

7. Eventually payment protocol messages finish so

                  Payment Handler sends Pay Receipt and optional
                  signature to the Consumer as proof of payment
   C <-------> P  PAYMENT RESPONSE. Components: Status, Pay Receipt;
                  Payment Note; Trading Role Data (optional);
                  Optional Offer Response Signature; Optional
                  Payment Receipt Signature that binds the payment
                  to the Offer

8. Consumer checks Payment Receipt is OK

*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*

                        Figure 3 Payment Exchange
 A Payment Exchange uses the following Trading Components that are
 passed between the Consumer, the Merchant and the Payment Handler:
 o  The Brand List Component contains a list of payment brands (for
    example, MasterCard, Visa, Mondex, GeldKarte), payment protocols
    (for example SET Version 1.0, Secure Channel Credit Debit (SCCD -
    the name used for a credit or debit card payment where

Burdett Informational [Page 22] RFC 2801 IOTP/1.0 April 2000

    unauthorised access to account information is prevented through
    use of secure channel transport mechanisms such as SSL/TLS) as
    well as currencies/amounts that apply. The Merchant sends the
    Brand List to the Consumer. The consumer compares the payment
    brands, protocols and currencies/amounts on offer with those that
    the Consumer supports and makes a selection.
 o  The Brand Selection Component contains the Consumer's selection.
    Payment brand, protocol, currency/amount and possibly protocol-
    specific information is sent back to the Merchant. This
    information may be used to change information in the Offer
    Exchange. For example, a merchant could choose to offer a discount
    to encourage the use of a store card.
 o  the Status component is used to indicate to the Payment Handler
    that an earlier exchange (e.g., an Offer Exchange) has
    successfully completed and by the Payment Handler to indicate the
    completion status of the Payment Exchange.
 o  The Organisation Components are generated by the Merchant. They
    contain details of the Merchant and Payment Handler Roles:
  1. the Merchant role is required so that the Payment Handler can

identify which Merchant initiated the payment. Typically, the

       result of the Payment Handler accepting (or making) a payment
       on behalf of the Merchant will be a credit or debit transaction
       to the Merchant's account held by the Payment Handler. These
       transactions are outside the scope of this version of IOTP
  1. the Payment Handler role is required so that the Payment

Handler can check that it is the correct Payment Handler to be

       used for the payment
 o  The Payment Component contains details of how much to pay, the
    currency and the payment direction
 o  The "Offer Response" Signature Component, if present, digitally
    signs all of the above components to ensure their integrity. Note
    that the Brand List and Brand Selection Components are not signed
    until the payment information is created (step 4 in the diagram)
 o  the Trading Role Data component contains from other roles (e.g., a
    Merchant) that needs to be  forwarded to the Payment Handler
 o  The Payment Scheme Component contains messages from the payment
    protocol used in the Trade. For example they could be SET
    messages, Mondex messages, GeldKarte Messages or one of the other
    payment methods supported by IOTP. The content of the Payment

Burdett Informational [Page 23] RFC 2801 IOTP/1.0 April 2000

    Scheme Component is defined in the supplements that describe how
    IOTP works with various payment protocols.
 o  The Payment Receipt Component contains a record of the payment.
    The content depends upon the payment protocol used.
 o  The "Payment Receipt" Signature Component provides proof of
    payment by digitally signing both the Payment Receipt Component
    and the Offer Response Signature. The signature on the offer
    digitally signs the Order, Organisation and Delivery Components
    contained in the Offer.  This signature effectively binds the
    payment to the offer.
 The example of a Payment Exchange above is the most general case.
 Simpler cases are also possible. For example, if the amount paid is
 not dependent on the payment brand and protocol selected then the
 payment information generated by step 3 can be sent to the Consumer
 at the same time as the Brand List Component generated by step 1.
 These and other variations are described in the Baseline Purchase
 IOTP Transaction (see section 9.1.8).

2.2.3 Delivery Exchange

 The goal of the Delivery Exchange is to cause purchased goods to be
 delivered to the consumer either online or via physical delivery. A
 second goal is to provide a "delivery note" to the consumer,
 providing details about the delivery, such as shipping tracking
 number. The result of the delivery may also be signed so that it can
 be used for customer care in the case of problems with physical
 delivery. The message flow is illustrated in the diagram below.

*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*

CONSUMER  DELIVERY
   |        HANDLER
   |  Merchant |

STEP | | | 1. Consumer decides to trade and sends information

                  about what to deliver and who is to take delivery,
                  to the Merchant e.g., using HTML.
   C --> M        Information on what is being delivered (outside
                  scope of IOTP)

2. Merchant checks the information provided by the

                  Consumer, adds information about how the delivery
                  will occur, information about the Organisations
                  involved in the delivery and optionally sings it
                  and sends it to the Consumer

Burdett Informational [Page 24] RFC 2801 IOTP/1.0 April 2000

   C <-- M        Components: Delivery; Organisations (Delivery
                  Handler, Deliver To); Order, Optional Offer
                  Response Signature

3. Consumer checks delivery information is OK,

                  obtains authorisation for the delivery, for
                  example by making a payment, and sends the
                  delivery information to the Delivery Handler
   C --------> D  DELIVERY REQUEST. Components: Status; Delivery,
                  Organisations: (Merchant, Delivery Handler,
                  DelivTo); Order, Trading Role Data (optional);
                  Optional Offer Response Signature, Optional
                  Payment Receipt Signature (from Payment Exchange)

4. Delivery Handler checks information and

                  authorisation. Starts or schedules delivery and
                  creates and then sends a delivery not tot the
                  Consumer which can optionally be signed.
   C <-------- D  DELIVERY RESPONSE. Components: Status; Delivery
                  Note, Trading Role Data (optional); Optional
                  Delivery Response Signature

5. Consumer checks delivery note is OK and accepts or

                  waits for delivery as described in the the Delivery
                  Note.

*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*

                       Figure 4 Delivery Exchange

A Delivery Exchange uses the following Trading Components that are passed between the Consumer, the Merchant and the Delivery Handler:

 o  the Status component is used to indicate to the Delivery Handler
    that an earlier exchange (e.g., an Offer Exchange or Payment
    Exchange) has successfully completed and by the Delivery Handler
    to indicate the completion status of the Delivery Exchange.
 o  The Organisation Component(s) contain details of the Deliver To,
    Delivery Handler and Merchant Roles:
  1. the Deliver To role indicates where the goods or services are

to be delivered to

Burdett Informational [Page 25] RFC 2801 IOTP/1.0 April 2000

  1. the Delivery Handler role is required so that the Delivery

Handler can check that she is the correct Delivery Handler to

       do the delivery
  1. the Merchant role is required so that the Delivery Handler can

identify which Merchant initiated the delivery

 o  The Order Component, contains information about the goods or
    services to be delivered
 o  The Delivery Component contains information about how delivery
    will occur, for example by post or using e-mail.
 o  The "Offer Response" Signature Component, if present, digitally
    signs all of the above components to ensure their integrity.
 o  The "Payment Receipt" Signature Component provides proof of
    payment by digitally signing the Payment Receipt Component and the
    Offer Signature. This is used by the Delivery Handler to check
    that delivery is authorised
 o  The Delivery Note Component contains customer care information
    related to a physical delivery, or alternatively the actual
    "electronic goods".  The Consumer's software does not interpret
    information about a physical delivery but should have the ability
    to display the information, both at the time of the delivery and
    later if the Consumer selects the Trade to which this delivery
    relates from a transaction list
 o  The "Delivery Response" Signature Component, if present, provides
    proof of the results of the Delivery by digitally signing the
    Delivery Note and any Offer Response or Payment Response
    signatures that the Delivery Handler received.

2.2.4 Authentication Exchange

 The goal of the Authentication Exchange is to allow one Organisation,
 for example a financial institution, to be able to check that another
 Organisation, for example a consumer, is who they appear to be.
 An Authentication Exchange involves:
 o  an Authenticator - the Organisation which is requesting the
    authentication, and
 o  an Authenticatee - the Organisation being authenticated.

Burdett Informational [Page 26] RFC 2801 IOTP/1.0 April 2000

 This is illustrated in the diagram below.

+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+* Organisation 1 (Authenticatee)

   |   Organisation 2
   |  (Authenticator)

STEP | | 1. First Organisation, e.g., a Consumer, takes an action (for

           example by pressing a button on an HTML page) which
           requires that the Organisation is authenticated
   1 --> 2 Need for Authentication (outside scope of IOTP)

2. The second Organisation generates an Authentication

           Request - including challenge data, and a list of the
           algorithms that may be used for the authentication -
           and/or a request for the Organisation information then
           sends it to the first Organisation
   1 <-- 2 AUTHENTICATION REQUEST. Components: Authentication
           Request, Trading Role Information Request

3. The first Organisation optionally checks any signature

           associated with the Authentication Request then uses the
           specified authentication algorithm to generate an
           Authentication Response which is sent back to the second
           Organisation together with details of any Organisation
           information requested
   1 --> 2 AUTHENTICATION RESPONSE. Component: Authentication
           Response, Organisation(s)

4. The Authentication Response is checked against the

           challenge data to check that the first Organisation is
           who they appear to be and the result recorded in a Status
           Component which is then sent back to the first
           Organisation.
   1 <-- 2 AUTHENTICATION STATUS. Component: Status

5. The first Organisation then optionally checks the results

           indicated by the Status and any associated signature and
           takes the appropriate action or stops.

*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*

                    Figure 5 Authentication Exchange

Burdett Informational [Page 27] RFC 2801 IOTP/1.0 April 2000

 An Authentication Exchange uses the following Trading Components that
 are passed between the two Organisations:
 o  the Authentication Request Component that requests an
    Authentication and indicates the authentication algorithm and
    optional challenge data to be used.
 o  A Trading Role Information Request Component that requests
    information about an Organisation, for example a ship to address.
 o  The Authentication Response Component which contains the challenge
    response generated by the recipient of the Authentication Request
    Component.
 o  Organisation Components that contain the result of the Trading
    Role Information Request
 o  the Status Component which contains the results of the second
    party's verification of the Authentication Response.

2.3 Scope of Baseline IOTP

 This specification describes the IOTP Transactions which make up
 Baseline IOTP. As described in the preface, IOTP will evolve over
 time. This section defines the initial conformance criteria for
 implementations that claim to "support IOTP."
 The main determinant on the scope of an IOTP implementation is the
 roles which the solution is designed to support. The roles within
 IOTP are described in more detail in section 2.1 Trading Roles. To
 summarise the roles are: Merchant, Consumer, Payment Handler,
 Delivery Handler and Customer Care Provider.
 Payment Handlers who can be of three types:
 o  those who accept a payment as part of a purchase or make a payment
    as part of a refund,
 o  those who accept value as part of a deposit transaction, or
 o  those that issue value a withdrawal transaction
 The following table defines, for each role, the IOTP Transactions and
 Trading Blocks which must be supported for that role.

Burdett Informational [Page 28] RFC 2801 IOTP/1.0 April 2000

                     Merchants
                      ECash    ECash
              Store   Value    Value    Consumer  Payment   Delivery
                      Issuer Acquirer             Handler   Handler

TRANSACTIONS

Purchase Must Must

                     Merchants
                      ECash    ECash
              Store   Value    Value    Consumer  Payment   Delivery
                      Issuer Acquirer             Handler   Handler

Refund Must b)

                                        Depends

Authentication May Must May b)

                                        Depends

Value Exchange May Must

Withdrawal Must b)

                                        Depends

Deposit Must b)

                                        Depends

Inquiry Must Must Must May Must Must

Ping Must Must Must May Must Must

TRADING BLOCKS

TPO Must Must Must Must

TPO Selection Must Must Must Must

Auth-Request a) a) a)

             Depends          Depends   Depends

Auth-Reply a) a) a)

             Depends          Depends   Depends

Offer Response Must Must Must Must

Burdett Informational [Page 29] RFC 2801 IOTP/1.0 April 2000

Payment Must Must Request

Payment Must Must Exchange

Payment Must Must Response

Delivery Must Must Request

Delivery Must Must Response

                     Merchants
                      ECash    ECash
              Store   Value    Value    Consumer  Payment   Delivery
                      Issuer Acquirer             Handler   Handler

Inquiry Must Must Must Must Must Must Request

Inquiry Must Must Must Must Must Must Response

Ping Request Must Must Must Must Must Must

Ping Response Must Must Must Must Must Must

Signature Must Must Must Limited Must Must

Error Must Must Must Must Must Must

 In the above table:
 o  "Must" means that a Trading Role must support the Transaction or
    Trading Block.
 o  "May" means that an implementation may support the Transaction or
    Trading Block at the option of the developer.
 o  "Depends" means implementation of the Transaction or Trading Block
    depends on one of the following conditions:
  1. if Baseline Authentication IOTP Transaction is supported;

Burdett Informational [Page 30] RFC 2801 IOTP/1.0 April 2000

  1. if required by a Payment Method as defined in its IOTP

Supplement document.

 o  "Limited" means the Trading Block must be understood and its
    content manipulated but not in every respect. Specifically, on the
    Signature Block, Consumers do not have to be able to validate
    digital signatures.
 An IOTP solution must support all the IOTP Transactions and Trading
 Blocks required by at least one role (column) as described in the
 above table for that solution to be described as "supporting IOTP".

3. Protocol Structure

 The previous section provided an introduction which explained:
 o  Trading Roles which are the different roles which Organisations
    can take in a trade: Consumer, Merchant, Payment Handler, Delivery
    Handler and Customer Care Provider, and
 o  Trading Exchanges where each Trading Exchange involves the
    exchange of data, between Trading Roles, in the form of a set of
    Trading Components.
 This section describes:
 o  how Trading Components are constructed into Trading Blocks and the
    IOTP Messages which are physically sent in the form of [XML]
    documents between the different Trading Roles,
 o  how IOTP Messages are exchanged between Trading Roles to create an
    IOTP Transaction
 o  the XML definitions of an IOTP Message including a Transaction
    Reference Block - an XML element which identifies an IOTP
    Transaction and the IOTP Message within it
 o  the definitions of the XML ID Attributes which are used to
    identify IOTP Messages, Trading Blocks and Trading Components and
    how these are referred to using Element References from other XML
    elements
 o  how extra XML Elements and new user defined values for existing
    IOTP codes can be used when Extending IOTP,
 o  how IOTP uses the Packaged Content Element to embed data such as
    payment protocol messages or detailed order definitions within an
    IOTP Message

Burdett Informational [Page 31] RFC 2801 IOTP/1.0 April 2000

 o  how IOTP Identifies Languages so that different languages can be
    used within IOTP Messages
 o  how IOTP handles both Secure and Insecure Net Locations when
    sending messages
 o  how an IOTP Transaction can be cancelled.

3.1 Overview

3.1.1 IOTP Message Structure

 The structure of an IOTP Message and its relationship with Trading
 Blocks and Trading Components is illustrated in the diagram below.

Burdett Informational [Page 32] RFC 2801 IOTP/1.0 April 2000

*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*

IOTP MESSAGE ←——— IOTP Message - an XML Document which is | transported between the Trading Roles |-Trans Ref Block ←—- Trans Ref Block - contains information which | | describes the IOTP Transaction and the IOTP | | Message. | |-Trans Id Comp. ←– Transaction Id Component - uniquely | | identifies the IOTP Transaction. The Trans Id | | Components are the same across all IOTP | | messages that comprise a single IOTP | | transaction. | |-Msg Id Comp. ←—- Message Id Component - identifies and | describes an IOTP Message within an IOTP | Transaction |-Signature Block ←—- Signature Block (optional) - contains one or | | more Signature Components and their | | associated Certificates | |-Signature Comp. ←- Signature Component - contains digital | | signatures. Signatures may sign digests of | | the Trans Ref Block and any Trading Component | | in any IOTP Message in the same IOTP | | transaction. | |-Certificate Comp. < Certificate Component (Optional) Used to check | the signature. |-Trading Block ←—— Trading Block - an XML Element within an IOTP | |-Trading Comp. Message that contains a predefined set of | |-Trading Comp. Trading Components | |-Trading Comp. | |-Trading Comp. ←– Trading Components - XML Elements within a | Trading Block that contain a predefined set |-Trading Block of XML elements and attributes containing | |-Trading Comp. information required to support a Trading | |-Trading Comp. Exchange | |-Trading Comp. | |-Trading Comp. | |-Trading Comp.

*-*-*-*-*-*–*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*

                    Figure 6 IOTP Message Structure
 The diagram also introduces the concept of a Transaction Reference
 Block.  This block contains, amongst other things, a globally unique
 identifier for the IOTP Transaction. Also each block and component is
 given an ID Attribute (see section 3.4) which is unique within an
 IOTP Transaction.  Therefore the combination of the ID attribute and

Burdett Informational [Page 33] RFC 2801 IOTP/1.0 April 2000

 the globally unique identifier in the Transaction Reference Block is
 sufficient to uniquely identify any Trading Block or Trading
 Component.

3.1.2 IOTP Transactions

 A predefined set of IOTP Messages exchanged between the Trading Roles
 constitute an IOTP Transaction. This is illustrated in the diagram
 below.

*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*

   CONSUMER                                              MERCHANT
                                                     Generate first
                                                      IOTP Message
                                 ---                        |
                                |   |                       v

Process incoming | I | ————-

IOTP Message &   <------------- |   | ------------ | IOTP Message |

generate next IOTP | | ————-

   Message                      | N |
      |                         |   |
      v                         |   |
-------------                   | T |              Process incoming

| IOTP Message | ————– | | ———–> IOTP Message &

  1. ———— | | generate next

| E | IOTP Message

                                |   |                       |
                                |   |                       v

Process incoming | R | ————-

 IOTP Message    <------------- |   | ------------ | IOTP Message |

generate last IOTP | | ————-

Message & stop                  | N |
      |                         |   |
      v                         |   |
-------------                   | E |                  Process last

| IOTP Message | ————– | | ————→ incoming IOTP

  1. ———— | | Message & stop

| | T | |

      v                         |   |                       v
     STOP                        ---                       STOP

*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-

                     Figure 7 An IOTP Transaction

Burdett Informational [Page 34] RFC 2801 IOTP/1.0 April 2000

 In the above diagram the Internet is shown as the transport
 mechanism.  This is not necessarily the case. IOTP Messages can be
 transported using a variety of transport mechanisms.
 The IOTP Transactions (see section 9) in this version of IOTP are
 specifically:
 o  Purchase. This supports a purchase involving an offer, a payment
    and optionally a delivery
 o  Refund. This supports the refund of a payment as a result of,
    typically, an earlier purchase
 o  Value Exchange. This involves two payments which result in the
    exchange of value from one combination of currency and payment
    method to another
 o  Authentication. This supports the remote authentication of one
    Trading Role by another Trading Role using a variety of
    authentication algorithms, and the provision of an Organisation
    Information about the Trading Role that is being authenticated for
    use in, for example, the creation of an offer
 o  Withdrawal. This supports the withdrawal of electronic cash from a
    financial institution
 o  Deposit. This supports the deposit of electronic cash at a
    financial institution
 o  Inquiry This supports inquiries on the status of an IOTP
    transaction which is either in progress or is complete
 o  Ping This supports a simple query which enables one IOTP aware
    application to determine whether another IOTP application running
    elsewhere is working or not.

3.2 IOTP Message

 As described earlier, IOTP Messages are [XML] documents which are
 physically sent between the different Trading Roles that are taking
 part in a trade.
 The XML definition of an IOTP Message is as follows.
 <!ELEMENT IotpMessage
    ( TransRefBlk,
      SigBlk?,
      ErrorBlk?,

Burdett Informational [Page 35] RFC 2801 IOTP/1.0 April 2000

      ( AuthReqBlk |
        AuthRespBlk |
        AuthStatusBlk |
        CancelBlk |
        DeliveryReqBlk |
        DeliveryRespBlk |
        InquiryReqBlk |
        InquiryRespBlk |
        OfferRespBlk |
        PayExchBlk |
        PayReqBlk |
        PayRespBlk |
        PingReqBlk |
        PingRespBlk |
        TpoBlk |
        TpoSelectionBlk
      )*
    ) >
 <!ATTLIST IotpMessage
   xmlns                     CDATA
   'iotp:ietf.org/iotp-v1.0'
 Content:
 TransRefBlk        This contains information which describes an IOTP
                    Message within an IOTP Transaction (see section
                    3.3 immediately below)
 AuthReqBlk,        These are the Trading Blocks.
 AuthRespBlk,
 DeliveryReqBlk,    The Trading Blocks present within an IOTP Message,
 DeliveryRespBlk    and the content of a Trading Block itself is
 ErrorBlk           dependent on the type of IOTP Transaction being
 InquiryReqBlk,     carried out - see the definition of each
 InquiryRespBlk,    transaction in section 9 Internet Open Trading
 OfferRespBlk,      Protocol Transactions.
 PayExchBlk,
 PayReqBlk,         Full definitions of each Trading Block are
 PayRespBlk,        described in section 8.
 PingReqBlk,
 PingRespBlk,
 SigBlk,
 TpoBlk,
 TpoSelectionBlk
 Attributes:
 xmlns              The [XML Namespace] definition for IOTP messages.

Burdett Informational [Page 36] RFC 2801 IOTP/1.0 April 2000

3.2.1 XML Document Prolog

 The IOTP Message is the root element of the XML document. It
 therefore needs to be preceded by an appropriate XML Document Prolog.
 For example:
 <?XML Version='1.0'?>
 <!DOCTYPE IotpMessage >
 <IotpMessage>
  ...
 </IotpMessage>

3.3 Transaction Reference Block

 A Transaction Reference Block contains information which identifies
 the IOTP Transaction and IOTP Message. The Transaction Reference
 Block contains:
 o  a Transaction Id Component which globally uniquely identifies the
    IOTP Transaction. The Transaction Id Components are the same
    across all IOTP messages that comprise a single IOTP transaction,
 o  a Message Id Component which provides control information about
    the IOTP Message as well as uniquely identifying the IOTP Message
    within an IOTP Transaction, and
 o  zero or more Related To Components which link this IOTP
    Transaction to either other IOTP Transactions or other events
    using the identifiers of those events.
 The definition of a Transaction Reference Block is as follows:
 <!ELEMENT TransRefBlk (TransId, MsgId, RelatedTo*) >
 <!ATTLIST TransRefBlk
  ID                 ID      #REQUIRED >
 Attributes:
 ID                 An identifier which uniquely identifies the
                    Transaction Reference Block within the IOTP
                    Transaction (see section 3.4 ID Attributes).
 Content:
 TransId            See 3.3.1 Transaction Id Component immediately
                    below.
 MsgId              See 3.3.2 Message Id Component immediately below.

Burdett Informational [Page 37] RFC 2801 IOTP/1.0 April 2000

 RelatedTo          See 3.3.3 Related To Component immediately below.

3.3.1 Transaction Id Component

 This contains information which globally uniquely identifies the IOTP
 Transaction. Its definition is as follows:
 <!ELEMENT TransId EMPTY >
 <!ATTLIST TransId
  ID                 ID      #REQUIRED
  Version            NMTOKEN #FIXED '1.0'
  IotpTransId        CDATA   #REQUIRED
  IotpTransType      CDATA   #REQUIRED
  TransTimeStamp     CDATA   #REQUIRED >
 Attributes:
 ID                 An identifier which uniquely identifies the
                    Transaction Id Component within the IOTP
                    Transaction.
 Version            This identifies the version of IOTP, and therefore
                    the structure of the IOTP Messages, which the IOTP
                    Transaction is using.
 IotpTransId        Contains data which uniquely identifies the IOTP
                    Transaction. It must conform to the rules for
                    Message Ids in [RFC 822].
 IotpTransTyp       This is the type of IOTP Transaction being carried
                    out. For Baseline IOTP it identifies a "standard"
                    IOTP Transaction and implies the sequence and
                    content of the IOTP Messages exchanged between the
                    Trading Roles. The valid values for Baseline IOTP
                    are:
                     o BaselineAuthentication
                     o BaselineDeposit
                     o BaselinePurchase
                     o BaselineRefund
                     o BaselineWithdrawal
                     o BaselineValueExchange
                     o BaselineInquiry
                     o BaselinePing
                    Values of IotpTransType are managed under the
                    procedure described in section 12 IANA
                    Considerations which also allows user defined
                    values of IotpTransType to be defined.

Burdett Informational [Page 38] RFC 2801 IOTP/1.0 April 2000

                    In later versions of IOTP, this list will be
                    extended to support different types of standard
                    IOTP Transaction. It is also likely to support the
                    type Dynamic which indicates that the sequence of
                    steps within the transaction are non-standard.
 TransTimeStamp     Where the system initiating the IOTP Transaction
                    has an internal clock, it is set to the time at
                    which the IOTP Transaction started in [UTC]
                    format.
                    The main purpose of this attribute is to provide
                    an alternative way of identifying a transaction by
                    specifying the time at which it started.
                    Some systems, for example, hand held devices may
                    not be able to generate a  time stamp. In this
                    case this attribute should contain the value "NA"
                    for Not Available.

3.3.2 Message Id Component

 The Message Id Component provides control information about the IOTP
 Message as well as uniquely identifying the IOTP Message within an
 IOTP Transaction. Its definition is as follows.
 <!ELEMENT MsgId EMPTY >
 <!ATTLIST MsgId
  ID                 ID      #REQUIRED
  RespIotpMsg        NMTOKEN #IMPLIED
  xml:lang           NMTOKEN #REQUIRED
  LangPrefList       NMTOKENS #IMPLIED
  CharSetPrefList    NMTOKENS #IMPLIED
  SenderTradingRoleRef NMTOKEN #IMPLIED
  SoftwareId         CDATA   #REQUIRED
  TimeStamp          CDATA   #IMPLIED >
 Attributes:
 ID                     An identifier which uniquely identifies the
                        IOTP Message within the IOTP Transaction (see
                        section 3.4 ID Attributes). Note that if an
                        IOTP Message is resent then the value of this
                        attribute remains the same.
 RespIotpMsg            This contains the ID attribute of the Message
                        Id Component of the IOTP Message to which this
                        IOTP Message is a response. In this way all

Burdett Informational [Page 39] RFC 2801 IOTP/1.0 April 2000

                        the IOTP Messages in an IOTP Transaction are
                        unambiguously linked together. This field is
                        required on every IOTP Message except the
                        first IOTP Message in an IOTP Transaction.
 SenderTradingRoleRef   The Element Reference (see section 3.5) of the
                        Trading Role which has generated the IOTP
                        message. It is used to identify the Net
                        Locations (see section 3.9) of the Trading
                        Role to which problems Technical Errors (see
                        section 4.1) with any of Trading Blocks should
                        be reported.
 Xml:lang               Defines the language used by attributes or
                        child elements within this component, unless
                        overridden by an xml:lang attribute on a child
                        element. See section 3.8 Identifying
                        Languages.
 LangPrefList           Optional list of Language codes that conform
                        to [XML] Language Identification. It is used
                        by the sender to indicate, in preference
                        sequence, the languages that the receiver of
                        the message ideally should use when generating
                        a response. There is no obligation on the
                        receiver to respond using one of the indicated
                        languages, but using one of the languages is
                        likely to provide an improved user experience.
 CharSetPrefList        Optional list of Character Set identifiers
                        that conform to [XML] Characters. It is used
                        by the sender to indicate, in preference
                        sequence, the character sets that the receiver
                        of the message ideally should use when
                        generating a response. There is no obligation
                        on the receiver to respond using one of the
                        character sets indicated, but using one of the
                        character sets is likely to provide an
                        improved user experience.
 SoftwareId             This contains information which identifies the
                        software which generated the IOTP Message. Its
                        purpose is to help resolve interoperability
                        problems that might occur as a result of
                        incompatibilities between messages produced by
                        different software. It is a single text string
                        in the language defined by xml:lang. It must
                        contain, as a minimum:

Burdett Informational [Page 40] RFC 2801 IOTP/1.0 April 2000

                        o the name of the software manufacturer
                        o the name of the software
                        o the version of the software, and
                        o the build of the software
 TimeStamp              Where the device sending the message has an
                        internal clock, it is set to the time at which
                        the IOTP Message was created in [UTC] format.

3.3.3 Related To Component

 The Related To Component links IOTP Transactions to either other IOTP
 Transactions or other events using the identifiers of those events.
 Its definition is as follows.
 <!ELEMENT RelatedTo (PackagedContent) >
 <!ATTLIST RelatedTo
  ID                 ID      #REQUIRED
  xml:lang           NMTOKEN #REQUIRED
  RelationshipType   NMTOKEN #REQUIRED
  Relation           CDATA   #REQUIRED
  RelnKeyWords       NMTOKENS #IMPLIED >
 Attributes:
 ID                 An identifier which uniquely identifies the
                    Related To Component within the IOTP Transaction.
 xml:lang           Defines the language used by attributes or child
                    elements within this component, unless overridden
                    by an xml:lang attribute on a child element. See
                    section 3.8 Identifying Languages.
 RelationshipType   Defines the type of the relationship. Valid values
                    are:
                     o IotpTransaction. in which case the Packaged
                       Content Element contains an IotpTransId of
                       another IOTP Transaction
                     o Reference in which case the Packaged Content
                       Element contains the reference of some other,
                       non-IOTP document.
                    Values of RelationshipType are controlled under
                    the procedures defined in section 12 IANA
                    Considerations which also allows user defined
                    values to be defined.

Burdett Informational [Page 41] RFC 2801 IOTP/1.0 April 2000

 Relation           The Relation attribute contains a phrase in the
                    language defined by xml:lang which describes the
                    nature of the relationship between the IOTP
                    transaction that contains this component and
                    another IOTP Transaction or other event. The exact
                    words to be used are left to the implementers of
                    the IOTP software.
                    The purpose of the attribute is to provide the
                    Trading Roles involved in an IOTP Transaction with
                    an explanation of the nature of the relationship
                    between the transactions.
                    Care should be taken that the words used to in the
                    Relation attribute indicate the "direction" of the
                    relationship correctly. For example: one
                    transaction might be a refund for another earlier
                    transaction. In this case the transaction which is
                    a refund should contain in the Relation attribute
                    words such as "refund for" rather than "refund to"
                    or just "refund".
 RelnKeyWords       This attribute contains keywords which could be
                    used to help identify similar relationships, for
                    example all refunds. It is anticipated that
                    recommended keywords will be developed through
                    examination of actual usage. In this version of
                    the specification there are no specific
                    recommendations and the keywords used are at the
                    discretion of implementers.
 Content:
 PackagedContent    The Packaged Content (see section 3.7) contains
                    data which identifies the related transaction. Its
                    format varies depending on the value of the
                    RelationshipType.

3.4 ID Attributes

 IOTP Messages, Blocks (i.e. Transaction Reference Blocks and Trading
 Blocks), Trading Components (including the Transaction Id Component
 and the Signature Component) and some of their child elements are
 each given an XML "ID" attribute which is used to identify an
 instance of these XML elements. These identifiers are used so that
 one element can be referenced by another. All these attributes are
 given the attribute name ID.

Burdett Informational [Page 42] RFC 2801 IOTP/1.0 April 2000

 The values of each ID attribute are unique within an IOTP transaction
 i.e. the set of IOTP Messages which have the same globally unique
 Transaction ID Component. Also, once the ID attribute of an element
 has been assigned a value it is never changed. This means that
 whenever an element is copied, the value of the ID attribute remains
 the same.
 As a result it is possible to use these IDs to refer to and locate
 the content of any IOTP Message, Block or Component from any other
 IOTP Message, Block or Component in the same IOTP Transaction using
 Element References (see section 3.5).
 This section defines the rules for setting the values for the ID
 attributes of IOTP Messages, Blocks and Components.

3.4.1 IOTP Message ID Attribute Definition

 The ID attribute of the Message Id Component of an IOTP Message must
 be unique within an IOTP Transaction. It's definition is as follows:
 IotpMsgId_value  ::= IotpMsgIdPrefix IotpMsgIdSuffix
 IotpMsgIdPrefix  ::= NameChar (NameChar)*
 IotpMsgIdSuffix  ::= Digit (Digit)*
 IotpMsgIdPrefix    Apart from messages which contain: an Inquiry
                    Request Trading Block, an Inquiry Response Trading
                    Block, a Ping Request Trading Block or a Ping
                    Response Trading Block; then the same prefix is
                    used for all messages sent by the Merchant or
                    Consumer role as follows:
                     o "M" - Merchant
                     o "C" - Consumer
                    For messages which contain an Inquiry Request
                    Trading Block or a Ping Request Trading Block, the
                    prefix is set to "I" for Inquiry.
                    For messages which contain an Inquiry Response
                    Trading Block or a Ping Response Trading Block,
                    the prefix is set to "Q".
                    The prefix for the other roles in a trade is
                    contained within the Organisation Component for
                    the role and are typically set by the Merchant.
                    The following is recommended as a guideline and
                    must not be relied upon:

Burdett Informational [Page 43] RFC 2801 IOTP/1.0 April 2000

                     o "P" - First (only) Payment Handler
                     o "R" - Second Payment Handler
                     o "D" - Delivery Handler
                     o "C" - Deliver To
                    As a guideline, prefixes should be limited to one
                    character.
                    NameChar has the same definition as the [XML]
                    definition of NameChar.
 IotpMsgIdSuffix    The suffix consists of one or more digits. The
                    suffix must be unique within a Trading Role within
                    an IOTP Transaction. The following is recommended
                    as a guideline and must not be relied upon:
                     o the first IOTP Message sent by a trading role
                       is given the suffix "1"
                     o the second and subsequent IOTP Messages sent
                       by the same trading role are incremented by one
                       for each message
                     o no leading zeroes are included in the suffix
                    Put more simply the Message Id Component of the
                    first IOTP Message sent by a Consumer would have
                    an ID attribute of, "C1", the second "C2", the
                    third "C3" etc.
                    Digit has the same definition as the [XML]
                    definition of Digit.

3.4.2 Block and Component ID Attribute Definitions

 The ID Attribute of Blocks and Components must also be unique within
 an IOTP Transaction. Their definition is as follows:
 BlkOrCompId_value ::= IotpMsgId_value "." IdSuffix
 IdSuffix ::= Digit (Digit)*
 IotpMsgId_value    The ID attribute of the Message ID Component of
                    the IOTP Message where the Block or Component is
                    first used.
                    In IOTP, Trading Components and Trading Blocks are
                    copied from one IOTP Message to another. The ID
                    attribute does not change when an existing Trading
                    Block or Component is copied to another IOTP
                    Message.

Burdett Informational [Page 44] RFC 2801 IOTP/1.0 April 2000

 IdSuffix           The suffix consists of one or more digits. The
                    suffix must be unique within the ID attribute of
                    the Message ID Component used to generate the ID
                    attribute. The following is recommended as a
                    guideline and must not be relied upon:
                     o the first Block or Component sent by a trading
                       role is given the suffix "1"
                     o the ID attributes of the second and subsequent
                       Blocks or Components are incremented by one for
                       each new Block or Component added to an IOTP
                       Message
                     o no leading zeroes are included in the suffix
                    Put more simply, the first new Block or Component
                    added to the second IOTP Message sent, for
                    example, by a consumer would have a an ID
                    attribute of "C2.1", the second "C2.2", the third
                    "C2.3" etc.
                    Digit has the same definition as the [XML]
                    definition of Digit.

Burdett Informational [Page 45] RFC 2801 IOTP/1.0 April 2000

3.4.3 Example of use of ID Attributes

 The diagram below illustrates how ID attribute values are used.

*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*

    1st  IOTP MESSAGE                          2nd IOTP MESSAGE
  (e.g., from Merchant to                    (e.g., from Consumer to
         Consumer                              Payment Handler)

IOTP MESSAGE IOTP MESSAGE * |-Trans Ref Block. ID=M1.1 |-Trans Ref Block.ID=C1.1* | |-Trans Id Comp. ID = M1.2 ————>| |-Trans Id Comp. | | Copy Element | | ID=M1.2 | |-Msg Id Comp. ID = M1 | |-Msg Id Comp. ID=C1 * | | |-Signature Block. ID=M1.8 |-Signature Block.ID=C1.5* | |-Sig Comp. ID=M1.15 ——————>| |-Comp. ID=M1.15 | Copy Element | |-Trading Block. ID=M1.3 |-Trading Block.ID=C1.2 * | |-Comp. ID=M1.4 ————————–>|-Comp. ID=M1.4 | | Copy Element | | |-Comp. ID=M1.5 ————————–>|-Comp. ID=M1.5 | | Copy Element | | |-Comp. ID=M1.6 |-Comp. ID=C1.3 * | |-Comp. ID=M1.7 |-Comp. ID=C1.4 * | |-Trading Block. ID=M1.9

  |-Comp. ID=M1.10                             * = new elements
  |-Comp. ID=M1.11
  |-Comp. ID=M1.12
  |-Comp. ID=M1.13

*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-

                 Figure 8 Example use of ID attributes

3.5 Element References

 A Trading Component or one of its child XML elements, may contain an
 XML attribute that refers to another Block (i.e. a Transaction
 Reference Block or a Trading Block) or Trading Component (including a
 Transaction Id and Signature Component). These Element References are
 used for many purposes, a few examples include:
 o  identifying an XML element whose Digest is included in a Signature
    Component,

Burdett Informational [Page 46] RFC 2801 IOTP/1.0 April 2000

 o  referring to the Payment Handler Organisation Component which is
    used when making a Payment
 An Element Reference always contains the value of an ID attribute of
 a Block or Component.
 Identifying the IOTP Message, Trading Block or Trading Component
 which is referred to by an Element Reference, involves finding the
 XML element which:
 o  belongs to the same IOTP Transaction (i.e. the Transaction Id
    Components of the IOTP Messages match), and
 o  where the value of the ID attribute of the element matches the
    value of the Element Reference.
 Note: The term "match" in this specification has the same definition
 as the [XML] definition of match.
 An example of "matching" an Element Reference is illustrated in the
 example below.

Burdett Informational [Page 47] RFC 2801 IOTP/1.0 April 2000

  • +*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*
       1st  IOTP MESSAGE                          2nd IOTP MESSAGE
     (e.g., from Merchant to                    (e.g., from Consumer to
            Consumer                              Payment Handler)
 IOTP MESSAGE                               IOTP MESSAGE
  |-Trans Ref Block. ID=M1.1     Trans ID    |-Trans RefBlock. ID=C1.1
  |  |-Trans Id Comp. ID = M1.2 <-Components-|->|-TransId Comp.ID=M1.2
  |  |                            must be    |  |
  |  |-Msg Id Comp. ID = M1      Identical   |  |-Msg Id Comp. ID=C1
  |                                  ^       |
  |-Signature Block. ID=M1.8         |       |-Signature Block.ID=C1.5
  |  |-Sig Comp. ID=M1.15            |       |  |-Comp. ID=M1.15
  |                                 AND      |
  |-Trading Block. ID=M1.3           |       |-Trading Block. ID=C1.2
  |  |-Comp. ID=M1.4                 |          |-Comp. ID=M1.4
  |  |                               v          |
  |  |-Comp. ID=M1.5 <-------- -ID Attribute    |-Comp. ID=M1.5
  |  |                          and El Ref      |
  |  |-Comp. ID=M1.6            values must     |-Comp. ID=C1.3
  |  |                             match--------|--> El Ref=M1.5
  |  |-Comp. ID=M1.7                            |-Comp. ID=C1.4
  |
  |-Trading Block. ID=M1.9
     |-Comp. ID=M1.10
     |-Comp. ID=M1.11
     |-Comp. ID=M1.12
     |-Comp. ID=M1.13
  • -*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-
                         Figure 9 Element References
 Note: Element Reference attributes are defined as "NMTOKEN" rather
 than "IDREF" (see [XML]). This is because an IDREF requires that the
 XML element referred to is in the same XML Document.  With IOTP this
 is not necessarily the case.

3.6 Extending IOTP

 Baseline IOTP defines a minimum protocol which systems supporting
 IOTP must be able to accept. As new versions of IOTP are developed,
 additional types of IOTP Transactions will be defined. In addition to
 this, Baseline and future versions of IOTP will support user
 extensions to IOTP through two mechanisms:

Burdett Informational [Page 48] RFC 2801 IOTP/1.0 April 2000

 o  extra XML elements, and
 o  new values for existing IOTP codes.

3.6.1 Extra XML Elements

 The XML element and attribute names used within IOTP constitute an
 [XML Namespace] as identified by the xmlns attribute on the
 IotpMessage element. This allows IOTP to support the inclusion of
 additional XML elements within IOTP messages through the use of [XML
 Namespaces].
 Using XML Namespaces, extra XML elements may be included at any level
 within an IOTP message including:
 o  new Trading Blocks
 o  new Trading Components
 o  new XML elements within a Trading Component.
 The following rules apply:
 o  any new XML element must be declared according to the rules for
    [XML Namespaces]
 o  new XML elements which are either Trading Blocks or Trading
    Components must contain an ID attributes with an attribute name of
    ID.
 In order to make sure that extra XML elements can be processed
 properly, IOTP reserves the use of a special attribute,
 IOTP:Critical, which takes the values True or False and may appear in
 extra elements added to an IOTP message.
 The purpose of this attribute is to allow an IOTP aware application
 to determine if the IOTP transaction can safely continue.
 Specifically:
 o  if an extra XML element has an "IOTP:Critical" attribute with a
    value of "True" and an IOTP aware application does not know how to
    process the element and its child elements, then the IOTP
    transaction has a Technical Error (see section 4.1) and must fail.
 o  if an extra XML element has an "IOTP:Critical" attribute with a
    value of "False" then the IOTP transaction may continue if the
    IOTP aware application does not know how to process it. In this
    case:

Burdett Informational [Page 49] RFC 2801 IOTP/1.0 April 2000

  1. any extra XML elements contained within an XML element defined

within the IOTP namespace, must be included with that element

       whenever the IOTP XML element is used or copied by IOTP
  1. the content of the extra element must be ignored except that it

must be included when it is used in the creation of a digest as

       part of the generation of a signature
 o  if an extra XML element has no "IOTP:Critical" attribute then it
    must be treated as if it had an "IOTP:Critical" attribute with a
    value of "True"
 o  if an XML element contains an "IOTP:Critical" attribute, then the
    value of that attribute is assumed to apply to all the child
    elements within that element
 In order to ensure that documents containing "IOTP:Critical" are
 valid, it is declared as part of the DTD for the extra element as:
 IOTP:Critical     (True | False ) 'True'

3.6.2 Opaque Embedded Data

 If IOTP is to be extended using Opaque Embedded Data then a Packaged
 Content Element (see section 3.7) should be used to encapsulate the
 data.

3.7 Packaged Content Element

 The Packaged Content element supports the concept of an embedded data
 stream, transformed to both protect it against misinterpretation by
 transporting systems and to ensure XML compatibility. Examples of its
 use in IOTP include:
 o  to encapsulate payment scheme messages, such as SET messages,
 o  to encapsulate a description of an order, a payment note, or a
    delivery note.
 In general it is used to encapsulate one or more data streams.
 This data stream has three standardised attributes that allow for
 identification, decoding and interpretation of the contents. Its
 definition is as follows.

Burdett Informational [Page 50] RFC 2801 IOTP/1.0 April 2000

 <!ELEMENT PackagedContent (#PCDATA) >
 <!ATTLIST PackagedContent
  Name             CDATA     #IMPLIED
  Content          NMTOKEN   "PCDATA"
  Transform (NONE|BASE64)    "NONE" >
 Attributes:
 Name               Optional. Distinguishes between multiple
                    occurrences of Packaged Content Elements at the
                    same point in IOTP. For example:
                      <ABCD>
                        <PackagedContent Name='FirstPiece'>
                          snroasdfnas934k
                        </PackagedContent>
                        <PackagedContent Name='SecondPiece'>
                          dvdsjnl5poidsdsflkjnw45
                        </PackagedContent>
                      </ABCD>
                    The name attribute may be omitted, for example if
                    there is only one Packaged Content element.
 Content            This identifies what type of data is contained
                    within the Content of the Packaged Content
                    Element. The valid values for the Content
                    attribute are as follows:
                     o PCDATA. The content of the Packaged Content
                       Element can be treated as PCDATA with no
                       further processing.
                     o MIME. The content of the Packaged Content
                       Element is a complete MIME item. Processing
                       should include looking for MIME headers inside
                       the Packaged Content Element.
                     o MIME:mimetype. The content of the Packaged
                       Content Element is MIME content, with the
                       following header "Content-Type: mimetype".
                       Although it is possible to have MIME:mimetype
                       with the Transform attribute set to NONE, it is
                       far more likely to have Transform attribute set
                       to BASE64. Note that if Transform is NONE is
                       used, then the entire content must still
                       conform to PCDATA. Some characters will need to
                       be encoded either as the XML default entities,
                       or as numeric character entities.

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                     o XML. The content of the Packaged Content
                       Element can be treated as an XML document.
                       Entities and CDATA sections, or Transform set
                       to BASE64, must be used to ensure that the
                       Packaged Content Element contents are
                       legitimate PCDATA.
                    Values of the Content attribute are controlled
                    under the procedures defined in section 12 IANA
                    Considerations which also allows user defined
                    values to be defined.
 Transform          This identifies the transformation that has been
                    done to the data before it was placed in the
                    content. Valid values are:
                     o NONE. The PCDATA content of the Packaged
                       Content Element is the correct representation
                       of the data. Note that entity expansion must
                       occur first (i.e. replacement of &amp; and
                       &#9;) before the data is examined. CDATA
                       sections may legitimately occur in a Packaged
                       Content Element where the Transform attribute
                       is set to NONE.
                     o BASE64. The PCDATA content of the Packaged
                       Content Element represents a BASE64 encoding of
                       the actual content.
 Content:
 PCDATA             This is the actual data which has been embedded.
                    The format of the data and rules on how to decode
                    it are contained in the Content and the Transform
                    attributes
 Note that any special details, especially custom attributes, must be
 represented at a higher level.

3.7.1 Packaging HTML

 The packaged content may contain HTML. In this case the following
 conventions are followed:
 o  references to any documents, images or other things, such as
    sounds or web pages, which can affect the recipient's
    understanding of the data which is being packaged must refer to
    other Packaged Elements contained within the same parent element,
    e.g., an Order Description

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 o  if more than one Packaged Content element is included within a
    parent element in order to meet the previous requirement, then the
    Name attribute of the top level Packaged Content from which
    references to all other Packaged Elements can be determined,
    should have a value of Main
 o  relative references to other documents, images, etc. from one
    Packaged Content element to another are realised by setting the
    value of the relative reference to the Name attribute of another
    Packaged Content element at the same level and within the same
    parent element
 o  no external references that require the reference to be resolved
    immediately should be used. As this could make the HTML difficult
    or impossible to display completely
 o  [MIME] is used to encapsulate the data inside each Packaged
    Element.  This means that the information in the MIME header used
    to identify the type of data which has been encapsulated and
    therefore how it should be displayed.
 If the above conventions are not followed by, for example, including
 external references which must be resolved, then the recipient of the
 HTML should be informed.
 Note: As an implementation guideline the values of the Name
 Attributes allocated to Packaged Content elements should make it
 possible to extract each Packaged Content into a directory and then
 display the HTML directly

3.7.2 Packaging XML

 Support for XML is recommended. When XML needs to be displayed, for
 example to display the content of an Order Description to a Consumer,
 then implementers should follow the latest recommendations of the
 World Wide Web Consortium.
 Note: At the time of writing this specification, standards are under
 development that specify XML style sheets that show how XML documents
 should be displayed. See:
 o "Extensible Stylesheet Language (XSL) Specification" at
   http://www.w3.org/TR/WD-xsl, and
 o "Associating stylesheets with XML documents" at
   http://www.w3.org/TR/xml-stylesheet.

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 Once these standards become W3C "Recommendations", then it is
 anticipated that this specification will be amended if practical.

3.8 Identifying Languages

 IOTP uses [XML] Language Identification to specify which languages
 are used within the content and attributes of IOTP Messages.
 The following principles have been used in order to determine which
 XML elements contain an xml:lang Attributes:
 o  a mandatory xml:lang attribute is contained on every Trading
    Component which contains attributes or content which may need to
    be displayed or printed in a particular language
 o  an optional xml:lang attribute is included on child elements of
    these Trading Components. In this case the value of xml:lang, if
    present, overrides the value for the Trading Component.
 xml:lang attributes which follow these principles are included in the
 Trading Components and their child XML elements defined in section 7.
 A sender of a message, typically a Consumer can indicate a preference
 for a language, and a character set by specifying a list of preferred
 languages/character sets in a Message Id Component (see section
 3.3.2).  Note that there is no obligation on the receiver of such a
 message to respond using one of the listed languages/character sets
 as they may not have the technology to be able to do it. It also
 means that the ability to handle these lists is not a requirement for
 conformance to this specification. However the ability to respond,
 for example using one of the stated languages/character sets is
 likely to provide a better user experience.

3.9 Secure and Insecure Net Locations

 IOTP contains several "Net Locations" which identify places where,
 typically, IOTP Messages may be sent. Net Locations come in two
 types:
 o  "Secure" Net Locations which are net locations where privacy of
    data is secured using, for example, encryption methods such as
    [SSL/TLS], and
 o  "Insecure" Net Locations where privacy of data is not assured.
 Note that either a Secure Net Location or an Insecure Net Location or
 both must be present.

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 If only one of the two Net Locations is present, then the one present
 must be used.
 Where both types of net location are present then either may be used
 depending on the preference of the sender of the message.

3.10 Cancelled Transactions

 Any Trading Role involved in an IOTP transaction may cancel that
 transaction at any time.

3.10.1 Cancelling Transactions

 IOTP Transactions are cancelled by sending an IOTP message containing
 just a Cancel Block with an appropriate Status Component to the other
 Trading Role involved in the Trading Exchange.
 Note: The Cancel Block can be sent asynchronously of any other IOTP
 Message. Specifically it can be sent either before sending or after
 receiving an IOTP Message from the other Trading Role
 If an IOTP Transaction is cancelled during a Trading Exchange (i.e.
 the interval between sending a "request" block and receiving the
 matching "response" block) then the Cancel Block is sent to the same
 location as the next IOTP Message in the Trading Exchange would have
 been sent.
 If a Consumer cancels a transaction after a Trading Exchange has
 completed (i.e. the "response" block for the Trading Exchange has
 been received), but before the IOTP Transaction has finished then the
 Consumer sends a Cancel Block with an appropriate Status Component to
 the net location identified by the SenderNetLocn or
 SecureSenderNetLocn contained in the Protocol Options Component (see
 section 7.1) contained in the TPO Block (see section 8.1) for the
 transaction. This is normally the Merchant Trading Role.
 A Consumer should not send a Cancel Block after the IOTP Transaction
 has completed. Cancelling a complete transaction should be treated as
 a technical error.
 After cancelling the IOTP Transaction, the Consumer should go to the
 net location specified by the CancelNetLocn attribute contained in
 the Trading Role Element for the Organisation that was sent the
 Cancel Block.
 A non-Consumer Trading Role should only cancel a transaction:
 o after a request block has been received and

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 o before the response block has been sent
 If a non-Consumer Trading Role cancels a transaction at any other
 time it should be treated by the recipient as an error.

3.10.2 Handling Cancelled Transactions

 If a Cancel Block is received by a Consumer at a point in the IOTP
 Transaction when cancellation is allowed, then the Consumer should
 stop the transaction.
 If a Cancel Block is received by a non-Consumer role, then the
 Trading Role should anticipate that the Consumer may go to the
 location specified by the CancelNetLocn attribute contained in the
 Trading Role Element for the Trading Role.

4. IOTP Error Handling

 IOTP is designed as a request/response protocol where each message is
 composed of a number of Trading Blocks which contain a number of
 Trading Components. There are several interrelated considerations in
 handling errors, re-transmissions, duplicates, and the like. These
 factors mean IOTP aware applications must manage message flows more
 complex than the simple request/response model. Also a wide variety
 of errors can occur in messages as well as at the transport level or
 in Trading Blocks or Components.
 This section describes at a high level how IOTP handles errors,
 retries and idempotency. It covers:
 o  the different types of errors which can occur. This is divided
    into:
  1. "technical errors" which are independent of the purpose of the

IOTP Message,

  1. "business errors" which indicate that there is a problem

specific to the process (e.g., payment or delivery) which is

       being carried out, and
 o  the depth of the error which indicates whether the error is at the
    transport, message or block/component level
 o  how the different trading roles should handle the different types
    of messages which they may receive.

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4.1 Technical Errors

 Technical Errors are those which are independent of the meaning of
 the message. This means, they can affect any attempt at IOTP
 communication.  Typically they are handled in a standard fashion with
 a limited number of standard options for the user. Specifically these
 are:
 o retrying the transmission, or
 o cancelling the transaction.
 When communications are operating sufficiently well, a technical
 error is indicated by an Error Component (see section 7.21) in an
 Error Block (see section 8.17) sent by the party which detected the
 error in an IOTP message to the party which sent the erroneous
 message.
 If communications are too poor, a message which was sent may not
 reach its destination. In this case a time-out might occur.
 The Error Codes associated with Technical Errors are recorded in the
 Error Component which lists all the different technical errors which
 can be set.

4.2 Business Errors

 Business Errors may occur when the IOTP messages are "technically"
 correct. They are connected with a particular process, for example,
 an offer, payment, delivery or authentication, where each process has
 a different set of possible business errors.
 For example, "Insufficient funds" is a reasonable payment error but
 makes no sense for a delivery while "Back ordered" is a reasonable
 delivery error but not meaningful for a payment. Business errors are
 indicated in the Status Component (see section 7.16) of a "response
 block" of the appropriate type, for example a Payment Response Block
 or a Delivery Response Block. This allows whatever additional
 response related information is needed to accompany the error
 indication.
 Business errors must usually be presented to the user so that they
 can decide what to do next. For example, if the error is insufficient
 funds in a Brand Independent Offer (see section 9.1.2.2), the user
 might wish to choose a different payment instrument/account of the
 same brand or a different brand or payment system. Alternatively, if

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 the IOTP based implementation allows it and it makes sense for that
 instrument, the user might want to put more funds into the
 instrument/account and try again.

4.3 Error Depth

 The three levels at which IOTP errors can occur are the transport
 level, the message level, and the block level. Each is described
 below.

4.3.1 Transport Level

 This level of error indicates a fundamental problem in the transport
 mechanism over which the IOTP communication is taking place.
 All transport level errors are technical errors and are indicated by
 either an explicit transport level error indication, such as a "No
 route to destination" error from TCP/IP, or by a time out where no
 response has been received to a request.
 The only reasonable automatic action when faced with transport level
 errors is to retry and, after some number of automatic retries, to
 inform the user.
 The explicit error indications that can be received are transport
 dependent and the documentation for the appropriate IOTP Transport
 supplement should be consulted for errors and appropriate actions.
 Appropriate time outs to use are a function of both the transport
 being used and of the payment system if the request encapsulates
 payment information. The transport and payment system specific
 documentation should be consulted for time out and automatic retry
 parameters.  Frequently there is no way to directly inform the other
 party of transport level errors but they should generally be logged
 and if automatic recovery is unsuccessful and there is a human user,
 the user should be informed.

4.3.2 Message Level

 This level of error indicates a fundamental technical problem with an
 entire IOTP message. For example, the XML is not "Well Formed", or
 the message is too large for the receiver to handle or there are
 errors in the Transaction Reference Block (see section 3.3) so it is
 not possible to figure out what transaction the message relates to.
 All message level errors are technical errors and are indicated by
 Error Components (see section 7.21) sent to the other party. The
 Error Component includes a Severity attribute which indicates whether

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 the error is a Warning and may be ignored, a TransientError which
 indicates that a retry may resolve the problem or a HardError in
 which case the transaction must fail.
 The Technical Errors (see section 7.21.2 Error Codes) that are
 Message Level errors are:
 o  XML not well formed. The document is not well formed XML (see
    [XML])
 o  XML not valid. The document is not valid XML (see [XML])
 o  block level technical errors (see section 4.3.3) on the
    Transaction Reference Block (see section 3.3) and the Signature
    Block only. Checks on these blocks should only be carried out if
    the XML is valid
 Note that checks on the Signature Block include checking, where
 possible, that each Signature Component is correctly calculated. If
 the Signature is incorrectly calculated then the data that should
 have been covered by the signature can not be trusted and must be
 treated as erroneous. A description of how to check a signature is
 correctly calculated is contained in section 6.2.

4.3.3 Block Level

 A Block level error indicates a problem with a block or one of its
 components in an IOTP message (apart from Transaction Reference or
 Signature Blocks). The message has been transported properly, the
 overall message structure and the block/component(s) including the
 Transaction Reference and Signature Blocks are meaningful but there
 is some error related to one of the other blocks.
 Block level errors can be either:
 o  technical errors, or
 o  business errors
 Technical Errors are further divided into:
 o  Block Level Attribute and Element Checks, and
 o  Block and Component Consistency Checks
 o  Transient Technical Errors

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 If a technical error occurs related to a block or component, then an
 Error Component is generated for return.

4.3.3.1 Block Level Attribute and Element Checks

 Block Level Attribute and Element Checks occur only within the same
 block. Checks which involve cross-checking against other blocks are
 covered by Block and Component Consistency Checks.
 The Block Level Attribute & Element checks are:
 o  checking that each attribute value within each element in a block
    conforms to any rules contained within this IOTP specification
 o  checking that the content of each element conforms to any rules
    contained within this IOTP specification
 o  if the previous checks are OK, then checking the consistency of
    attribute values and element content against other attribute
    values or element content within any other components in the same
    block.

4.3.3.2 Block and Component Consistency Checks

 Block and Component Consistency Checks consist of:
 o  checking that the combination of blocks and/or components present
    in the IOTP Message are consistent with the rules contained within
    this IOTP specification
 o  checking for consistency between attributes and element content
    within the blocks within the same IOTP message.
 o  checking for consistency between attributes and elements in blocks
    in this IOTP message and blocks received in earlier IOTP messages
    for the same IOTP transaction
 If the block passes the "Block Level Attribute and Element Checks"
 and the "Block and Component Consistency Checks" then it is processed
 either by the IOTP Aware application or perhaps by some "back-end"
 system such as a payment server.

4.3.3.3 Transient Technical Errors

 During the processing of the Block some temporary failure may occur
 that can potentially be recovered by the other trading role re-
 transmitting, at some slightly later time, the original message that
 they sent.  In this case the other role is informed of the Transient

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 Error by sending them an Error Component (see section 7.21) with the
 Severity Attribute set to TransientError and the MinRetrySecs
 attribute set to some value suitable for the Transport Mechanism
 and/or payment protocol being used (see appropriate Transport and
 payment protocol Supplements).
 Note that transient technical errors can be generated by any of the
 Trading Roles involved in transaction.

4.3.3.4 Block Level Business Errors

 If a business error occurs in a process such as a Payment or a
 Delivery, then the appropriate type of response block is returned
 containing a Status Component (see section 7.16) with the
 ProcessState attribute set to Failed and the CompletionCode
 indicating the nature of the problem.
 Some business errors may be "transient" in that the Consumer role may
 be able to recover and complete the transaction in some other way.
 For example if the Credit Card that a consumer provided had
 insufficient funds for a purchase, then the Consumer may recover by
 using a different credit card.
 Recovery from "transient" business errors is dependent on the
 CompletionCode. See the definition of the Status Component for what
 is possible.
 Note that no Error Component or Error Block is generated for business
 errors.

4.4 Idempotency, Processing Sequence, and Message Flow

 IOTP messages are actually a combination of blocks and components as
 described in 3.1.1 IOTP Message Structure. Especially in future
 extensions of IOTP, a rich variety of combinations of such blocks and
 components can occur. It is important that the multiple
 transmission/receipt of the "same" request for an action that will
 change state does not result in that action occurring more than once.
 This is called idempotency. For example, a customer paying for an
 order would want to pay the full amount only once. Most network
 transport mechanisms have some probability of delivering a message
 more than once or not at all, perhaps requiring retransmission. On
 the other hand, a request for status can reasonably be repeated and
 should be processed fresh each time it is received.

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 Correct implementation of IOTP can be modelled by a particular
 processing order as detailed below. Any other method that is
 indistinguishable in the messages sent between the parties is equally
 acceptable.

4.5 Server Role Processing Sequence

 "Server roles" are any Trading Role which is not the Consumer role.
 They are "Server roles" since they typically receive a request which
 they must service and then produce a response. However server roles
 can also initiate transactions. More specifically Server Roles must
 be able to:
 o  Initiate a transaction (see section 4.5.1). These are divided
    into:
  1. payment related transactions and
  1. infrastructure transactions
 o  Accept and process a message received from another role (see
    section 4.5.2). This includes:
  1. identifying if the message belongs to a transaction that has

been received before

  1. handling duplicate messages
  1. generating Transient errors if the servers that process the

input message are too busy to handle it

  1. processing the message if it is error free, authorised and, if

appropriate, producing a response to send back to the other

       role
 o  Cancel a current transaction if requested (see section 4.5.3)
 o  Re-transmit messages if a response was expected but has not been
    received in a reasonable time (see section 4.5.4).

4.5.1 Initiating Transactions

 Server Roles may initiate a variety of different types of
 transaction.  Specifically:
 o  an Inquiry Transaction (see section 9.2.1)
 o  a Ping Transaction (see section 9.2.2)

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 o  an Authentication Transaction (see section 9.1.6)
 o  a Payment Related Transaction such as:
  1. a Deposit (see section 9.1.7)
  1. a Purchase (see section 9.1.8)
  1. a Refund (see section 9.1.9)
  1. a Withdrawal (see section 9.1.10)
  1. a Value Exchange (see section 9.1.11)

4.5.2 Processing Input Messages

 Processing input messages involves the following:
 o  checking the structure and identity of the message
 o  checking for and handling duplicate messages
 o  processing non-duplicate original messages which includes:
  1. checking for errors, then if no errors are found
  1. processing the message to produce an output message if

appropriate

 Each of these is discussed in more detail below.

4.5.2.1 Checking Structure and Message Identity

 It is critical to check that the message is "well formed" XML and
 that the transaction identifier (IotpTransId attribute on the TransId
 Component) within the IOTP message can be successfully identified
 since an IotpTransId will be needed to generate a response.
 If the input message is not well formed then generate an Error
 Component with a Severity of HardError and ErrorCode of
 XmlNotWellFrmd.
 If the message is well formed but the IotpTransId cannot be
 identified then generate an ErrorComponent with:
 o  a Severity of HardError and an ErrorCode of AttMissing,

Burdett Informational [Page 63] RFC 2801 IOTP/1.0 April 2000

 o  a PackagedContent containing "IotpTransId" - the missing
    attribute.
 Insert the Error Component inside an Error Block with a new
 TransactionId component with a new IotpTransId and return it to the
 sender of the original message.

4.5.2.2 Checking/Handling Duplicate Messages

 If the input message can be identified as potentially a valid input
 message then check to see if an "identical" input message has been
 received before. Identical means that all blocks, components,
 elements, attribute values and element content in the input message
 are the same.
 Note: The recommended way of checking for identical messages is to
 check for equal values of their [DOM-HASH]
 If an identical message has been received before then check to see if
 the processing of the previous message has completed.
 If processing has not completed then generate an Error Component with
 a Severity of Transient Error and an Error Code of MsgBeingProc to
 indicate the message is being processed and send it back to the
 sender of the Input Message requesting that the original message be
 resent after an appropriate period of time.
 Otherwise, if processing has completed and resulted in an output
 message then retrieve the last message that was sent and send it
 again.
 If the message is not a duplicate then it should be processed.

4.5.2.3 Processing Non-Duplicate Message

 Once it's been established that the message is not a duplicate, then
 it can be processed. This involves:
 o  checking that a server is available to handle the message,
    generating a Transient Error if it is not
 o  checking the Transaction is Not Already in error or cancelled
 o  validating the input message. This includes:
  1. checking for message level errors
  1. checking for block level errors

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  1. checking any encapsulated data
 o  checking for errors in the sequence that blocks have been received
 o  generating error components for any errors that result
 o  if neither hard errors nor transient errors result, then
    processing the message and generating an output message, if
    required, for return to the sender of the Input Message
 Note: This approach to handling of duplicate input messages means, if
 absolutely "identical" messages are received then absolutely
 "identical" messages are returned. This also applies to Inquiry and
 Ping transactions when in reality the state of a transaction or the
 processing ability of the servers may have changed. If up-to-date
 status of transactions or servers is required, then an IOTP
 transaction with a new value for the ID attribute of the MsgId
 component must be used.
 Each of the above steps is discussed below.
 CHECKING A SERVER IS AVAILABLE
 The process that is handling the input message should check that the
 rest of the system is not so busy that a response in a reasonable
 time cannot be produced.
 If the server is too busy, then it should generate an Error Component
 with a Severity of Transient Error and an Error Code of SystemBusy
 and send it back to the sender of the Input Message requesting that
 the original message be resent after an appropriate period of time.
 Note: Some servers may occasionally become very busy due to
 unexpected increases in workload. This approach allows short peaks in
 workloads to be handled by delaying the input of messages by asking
 the sender of the message to resubmit later.
 CHECKING THE TRANSACTION IS NOT ALREADY IN ERROR OR CANCELLED
 Check that:
 o  previous messages received or sent did not contain or result in
    Hard Errors, and
 o  the Transaction has not been cancelled by either the Consumer or
    the Server Trading Role

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 If it has then, ignore the message. A transaction with hard errors or
 that has been cancelled, cannot be restarted.
 CHECK FOR MESSAGE AND BLOCK LEVEL ERRORS
 If the transaction is still OK then check for message level errors.
 This involves:
 o  checking the XML is valid
 o  checking that the elements, attributes and content of the
    Transaction Reference Block are without error and conform to this
    specification
 o  checking the digital signature which involves:
  1. checking that the Signature value is correctly calculated, and
  1. the hash values in the digests are correctly calculated where

the source of the hash value is available.

 Checking for block level errors involves:
 o  checking within each block (apart from the Transaction Reference
    Block) that:
  1. the attributes, elements and element contents are valid
  1. the values of the attributes, elements and element contents are

consistent within the block

 o  checking that the combination of blocks are valid
 o  checking that the values of the attribute, elements and element
    contents are consistent between the blocks in the input message
    and blocks in earlier messages either sent or received. This
    includes checking that the presence of a block is valid for a
    particular transaction type
 If the message contains any encapsulated data, then if possible check
 the encapsulated data for errors using additional software to check
 the data where appropriate.

4.5.2.4 Check for Errors in Block Sequence

 Note: For reasons of brevity, the following explanations of how to
 check for errors in Block sequence, the phrase "refers to an IOTP
 transaction" is interpreted as "is contained in an IOTP Message where

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 the Trans Ref Block contains an IotpTransId that refers to". So, for
 example, " If an Error or Cancel Block refers to an IOTP transaction
 that is not recognised then ..."  should be interpreted as " If an
 Error or Cancel Block is contained in an IOTP Message where the Trans
 Ref Block contains an IotpTransId that refers to an IOTP transaction
 that is not recognised then ...
 Errors in the sequence that blocks arrive depends on the block.
 Blocks where checking for sequence is required are:
 o  Error and Cancel Blocks. If an Error or Cancel Block refers to an
    IOTP transaction that is not recognised then it is a Hard Error.
    Do not return an error if Error or Cancel Blocks have been
    received for the IOTP Transaction before to avoid looping.
 o  Inquiry Request and Response Blocks. If an Inquiry Request or an
    Inquiry Response Block refers to an IOTP transaction that is not
    recognised then it is a Hard Error
 o  Authentication Request Block. If an Authentication Request Block
    refers to an IOTP transaction that is recognised it is a Hard
    Error
 o  Authentication Response Block. Check as follows:
  1. if an Authentication Response Block does not refer to an IOTP

transaction that is recognised it is a Hard Error, otherwise

  1. if the Authentication Response Block doesn't refer to an

Authentication Request that had been previously sent then it is

       a Hard Error, otherwise
  1. if an Authentication Response for the same IOTP transaction has

been received before and the Authentication was successful then

       it is a Hard Error.
 o  Authentication Status Block. Check as follows:
  1. if an Authentication Status Block does not refer to an IOTP

transaction that is recognised it is a Hard Error, otherwise

  1. if the Authentication Status Block doesn't refer to an

Authentication Response that had been previously sent then it

       is a Hard Error, otherwise
  1. if an Authentication Status for the same IOTP transaction has

been received before then it is a Warning Error

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 o  TPO Selection Block (Merchant only). Check as follows:
  1. if the TPO Selection Block doesn't refer to an IOTP Transaction

that is recognised then it is a Hard Error, otherwise

  1. if the TPO Selection Block refers to an IOTP Transaction where

a TPO Block and Offer Response (in one message) had previously

       been sent then it is a Hard Error, otherwise
  1. if the TPO Selection Block does not refer to an IOTP

Transaction where a TPO Block only (i.e. without an Offer

       Response) had previously been sent then it is a Hard Error,
       otherwise
  1. if a TPO Selection Block for the same TPO Block has been

received before then it is a Hard Error

 o  Payment Request Block (Payment Handler only). Check as follows:
  1. if the Payment Request Block refers to an IOTP Transaction that

is not recognised then its OK, otherwise

  1. if the Payment Request Block refers to IOTP Transaction that

was not for a Payment then it is a Hard Error, otherwise

  1. if there was a previous payment that failed with a non-

recoverable Completion Code then it is a Hard Error, otherwise

  1. if a previous payment is still in progress then it is a Hard

Error

 o Payment Exchange Block (Payment Handler only). Check as follows:
  1. if the Payment Exchange Block doesn't refer to an IOTP

Transaction that is recognised then it is a Hard Error,

       otherwise
  1. if the Payment Exchange doesn't refer to an IOTP Transaction

where a Payment Exchange had previously been sent then it a

       Hard Error
 o  Delivery Request (Delivery Handler Only). If the Delivery Request
    Block refers to an IOTP Transaction that is recognised by the
    Server then it is a Hard Error

Burdett Informational [Page 68] RFC 2801 IOTP/1.0 April 2000

 If any Error Components have been generated then collect them into an
 Error Block for sending to the sender of the Input message. Note that
 Error Blocks should be sent back to the sender of the message and to
 the ErrorLogNetLocn for the Trading Role of the sender if one is
 specified.
 Note: The above checking on the sequence of Authentication Responses
 and Payment Requests supports the Consumer re-submitting a repeat
 action request since the previous one failed, for example:
 o  because they did not know the correct response (e.g., a password)
    on an authentication or,
 o  they were unable to pay as there were insufficient funds on a
    credit card
 PROCESS THE ERROR FREE INPUT MESSAGE
 If the input message passes the previous checks then it can be
 processed to produce an output message if required. Note that:
 o  Inquiry Requests on Ping Transactions should be ignored
 o  if the Input message contains an Error Block with a Transient
    Error then wait for the required time then resend the previous
    message, if a response to the earlier message has not been
    received
 o  if the input message contains a Error Component with a  HardError
    or a Cancel Block then stop all further processing of the
    transaction. This includes suppressing the sending of any messages
    currently being generated or responding to any new non-duplicate
    messages that are received
 o  processing of encapsulated messages (e.g., Payment Protocol
    Messages) may result in additional transient errors
 o  a digital signature can only safely be generated once all the
    blocks and components have been generated and it is known which
    elements in the message need to be signed.
 If an output message is generated then it should be saved so that it
 can be resent as required if an identical input message is received
 again.  Note that output messages that contain transient errors are
 not saved so that they can be processed afresh when the input message
 is received again.

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4.5.3 Cancelling a Transaction

 This process is used to cancel a transaction running on an IOTP
 server.  It is initiated by some other process as a result of an
 external request from another system or server that is being run by
 the same Trading Role.  The processing required is as follows:
 o  if the IotpTransId of the transaction to be cancelled is not
    recognised, or complete then fail the request, otherwise
 o  if the IotpTransId refers to a Ping Transaction then fail the
    request, otherwise
 o  determine which Document Exchange to cancel and generate a Cancel
    Block and send it to the other party
 Note: Cancelling a transaction on an IOTP server typically arises for
 a business reason. For example a merchant may have attempted
 authentication several times without success and as a result decides
 to cancel the transaction. Therefore the process that decides to take
 this action needs to send a message from the process/server that made
 the business decision to the IOTP server with the instruction that
 the IOTP transaction should be cancelled.

4.5.4 Retransmitting Messages

 The server should periodically check for transactions where a message
 is expected in return but none has been received after a time that is
 dependent on factors such as:
 o  the Transport Mechanism being used;
 o  the time required to process encapsulated messages (e.g., Payment
    messages) and
 o  whether or not human input is required.
 If no message has been received the original message should be
 resent.  This should occur up to a maximum number of times dependent
 on the reliability of the Transport Mechanism being used.
 If no response is received after the required time then the
 Transaction should be "timed out". In this case, set the process
 state of the transaction to Failed, and a completion code of either:
 o  TimedOutRcvr if the transaction can potentially recovered later,
    or

Burdett Informational [Page 70] RFC 2801 IOTP/1.0 April 2000

 o  TimedOutNoRcvr if the transaction is non-recoverable

4.6 Client Role Processing Sequence

 The "Client role" in IOTP is the Consumer Trading Role.
 Note: A company or Organisation that is a Merchant, for example, may
 take on the Trading Role of a Consumer when making purchases or
 downloading or withdrawing electronic cash.
 More specifically the Consumer Role must be able to:
 o  Initiate a transaction (see section 4.6.1). These are divided
    into:
  1. payment related transactions and
  1. infrastructure transactions
 o  Accept and process a message received from another role (see
    section 4.6.2). This includes:
  1. identifying if the message belongs to a transaction that has

been received before

  1. handling duplicate messages
  1. generating Transient errors if the servers that process the

input message are too busy to handle it

  1. processing the message if it is error free and, if appropriate,

producing a response to send back to the other role

 o  Cancel a current transaction if requested, for example by the User
    (see section 4.6.3)
 o  Re-transmit messages if a response was expected but has not been
    received in a reasonable time (see section 4.6.4).

4.6.1 Initiating Transactions

 The Consumer Role may initiate a number of different types of
 transaction. Specifically:
 o an Inquiry Transaction (see section 9.2.1)
 o a Ping Transaction (see section 9.2.2)

Burdett Informational [Page 71] RFC 2801 IOTP/1.0 April 2000

 o an Authentication Transaction (see section 9.1.6)

4.6.2 Processing Input Messages

 Processing of Input Messages for a Consumer Role is the same as for
 an IOTP Server (see section 4.5.2) except in the area of checking for
 Errors in Block Sequence (for an IOTP Server see section 4.5.2.4).
 This is described below
 Note: The description of the processing for an IOTP Server includes
 consideration of multi-threading of input messages and multi-tasking
 of requests. For the Consumer Role - particularly if running on a
 stand-alone system such as a PC - use of multi-threading is a
 decision of the implementer of the consumer role IOTP solution.

4.6.2.1 Check for Errors in Block Sequence

 The handling of the following blocks is the same as for an IOTP
 Server (see section 4.5.2.4) except that the Consumer Role is
 substituted for IOTP Server Role:
 o Error and Cancel Blocks,
 o Inquiry Request and Response Blocks,
 o Authentication Request, Response and Status Blocks.
 For the other blocks a Consumer role might receive, the potential
 errors in the sequence that blocks arrive depends on the block.
 Blocks where checking for sequence is required are:
 o  TPO Block. Check as follows:
  1. if the input message also contains an Authentication Request

block and an Offer Response Block then there is a Hard Error,

       otherwise
  1. if the input message also contains an Authentication Request

block and Authentication Status block then there is Hard Error

       otherwise,
  1. if the input message also contains an Authentication Request

block and the IOTP Transaction is recognised by the Consumer

       role's system, then there is a Hard Error, otherwise

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  1. if the input message also contains an Authentication Status

block and the IOTP Transaction is not recognised by the

       Consumer role's system then there is a Hard Error, otherwise
  1. if input message also contains an Authentication Status Block

and the Authentication Status Block has not been sent after an

       earlier Authentication Response message then there is a hard
       error
  1. if input message also contains an Offer Response Block and the

IOTP Transaction is recognised by the Consumer role's system

       then there is a Hard Error, otherwise
  1. if the TPO Block occurs on its own and the IOTP Transaction is

recognised by the Consumer role's system then there is a Hard

       Error
 o Offer Response Block. Check as follows:
  1. if the Offer Response Block is part of a Brand Independent

Offer Exchange (see section 9.1.2.2) then there is no sequence

       checking as it is part of the first message received, otherwise
  1. if the Offer Response Block is not part of an IOTP Transaction

that is recognised by the Consumer role then there is a Hard

       Error, otherwise
  1. if the Offer Response Block does not refer to an IOTP

transaction where a TPO Selection Block was the last message

       sent then there is a Hard Error
 o  Payment Exchange Block. Check as follows:
  1. if the Payment Exchange Block doesn't refer to an IOTP

Transaction that is recognised by the Consumer role's system

       then there is a Hard Error, otherwise
  1. if the Payment Exchange doesn't refer to an IOTP Transaction

where either a Payment Request or a Payment Exchange block was

       most recently sent then there is a Hard Error
 o  Payment Response Block. Check as follows:
  1. if the Payment Response Block doesn't refer to an IOTP

Transaction that is recognised by the Consumer role's system

       then there is a Hard Error, otherwise

Burdett Informational [Page 73] RFC 2801 IOTP/1.0 April 2000

  1. if the Payment Response doesn't refer to an IOTOP Transaction

where either a Payment Request or a Payment Exchange block was

       most recently sent then there is a Hard Error
 o  Delivery Response Block. Check as follows:
  1. if the Delivery Response Block doesn't refer to an IOTP

Transaction that is recognised by the Consumer role's system

       then there is a Hard Error, otherwise
  1. If the Delivery Response doesn't refer to an IOTP Transaction

where either a Payment Request or a Payment Exchange block was

       most recently sent then there is a Hard Error

4.6.3 Cancelling a Transaction

 This process cancels a current transaction on an Consumer role's
 system as a result of an external request from the user, or another
 system or server in the Consumer's role. The processing is the same
 as for an IOTP Server (see section 4.5.3).

4.6.4 Retransmitting Messages

 The process of retransmitting messages is the same as for an IOTP
 Server (see section 4.5.4).

5. Security Considerations

 This section considers, from an IETF perspective how IOTP addresses
 security. The next section (see section 6. Digital Signatures and
 IOTP) describes how IOTP uses Digital Signatures when these are
 needed.
 This section covers:
 o determining whether to use digital signatures
 o data privacy, and
 o payment protocol security.

5.1 Determining whether to use digital signatures

 The use of digital signatures within IOTP are entirely optional. IOTP
 can work successfully entirely without the use of digital signatures.
 Ultimately it is up to the Merchant, or other trading role, to decide
 whether IOTP Messages will include signatures, and for the Consumer

Burdett Informational [Page 74] RFC 2801 IOTP/1.0 April 2000

 to decide whether carrying out a transaction without signatures is an
 acceptable risk. If Merchants discover that transactions without
 signatures are not being accepted, then they will either:
 o start using signatures,
 o find a method of working which does not need signatures, or
 o accept a lower volume and value of business.
 A non-exhaustive list of the reasons why digital signatures might be
 used follows:
 o  the Merchant (or other trading role) wants to demonstrate that
    they can be trusted. If, for example, a merchant generates an
    Offer Response Signature (see section 7.19.2) using a certificate
    from a trusted third party, known to the Consumer, then the
    Consumer can check the signature and certificate and so more
    reasonably rely on the offer being from the actual Organisation
    the Merchant claims to be. In this case signatures using
    asymmetric cryptography are likely to be required
 o  the Merchant, or other Trading Role, want to generate a record of
    the transaction that is fit for a particular purpose. For example,
    with appropriate trust hierarchies, digital signatures could be
    checked by the Consumer to determine:
  1. if it would be accepted by tax authorities as a valid record of

a transaction, or

  1. if some warranty, for example from a "Better Business Bureau"

orsimilar was being provided

 o  the Payment Handler, or Delivery Handler, needs to know that the
    request is unaltered and authorised. For example, in IOTP, details
    of how much to pay is sent to the Consumer in the Offer Response
    and then forwarded to the Payment Handler in a Payment Request. If
    the request is not signed, the Consumer could change the amount
    due by, for example, removing a digit. If the Payment Handler has
    no access to the original payment information in the Offer
    Response, then, without signatures, the Payment Handler cannot be
    sure that the data has not been altered. Similarly, if the payment
    information is not digitally signed, the Payment Handler cannot be
    sure who is the Merchant that is requesting the payment
 o  a Payment Handler or Delivery Handler wants to provide a non-
    refutable record of the completion status of a Payment or
    Delivery. If a Payment Response or Delivery Response is signed,

Burdett Informational [Page 75] RFC 2801 IOTP/1.0 April 2000

    then the Consumer can later use the record of the Payment or
    Delivery to prove that it occurred.  This could be used, for
    example, for customer care purposes.
 A non-exhaustive list of the reasons why digital signatures might not
 be used follows:
 o  trading roles are combined therefore changes to data made by the
    consumer can be detected. One of the reasons for using signatures
    is so that one trading role can determine if data has been changed
    by the Consumer or some other party. However if the trading roles
    have access to the necessary data, then it might be possible to
    compare, for example, the payment information in the Payment
    Request with the payment information in the Offer Response. Access
    to the data necessary could be realised by, for example, the
    Merchant and Payment Handler roles being carried out by the same
    Organisation on the same system, or the Merchant and Payment
    Handler roles being carried out on different systems but the
    systems can communicate in some way. (Note this type of
    communication is outside the current scope of IOTP)
 o  the processing cost of the cryptography is too high. For example,
    if a payment is being made of only a few cents, the cost of
    carrying out all the cryptography associated with generating and
    checking digital signatures might make the whole transaction
    uneconomic. Co-locating trading roles, could help avoid this
    problem.

5.2 Symmetric and Asymmetric Cryptography

 The advantage of using symmetric keys with IOTP is that no Public Key
 Infrastructure need be set up and just the Merchant, Payment Handler
 and Delivery Handler need to agree on the shared secrets to use.
 However the disadvantage of symmetric cryptography is that the
 Consumer cannot easily check the credentials of the Merchant, Payment
 Handler, etc. that they are dealing with. This is likely to reduce,
 somewhat, the trust that the Consumer will have carrying out the
 transaction.
 However it should be noted that even if asymmetric cryptography is
 being used, the Consumer does not NEED to be provided with any
 digital certificates as the integrity of the transaction is
 determined by, for example, the Payment Handler checking the Offer
 Response Signature copied to the Payment Request.
 Note that symmetric, asymmetric or both types of cryptography may be
 used in a single transaction.

Burdett Informational [Page 76] RFC 2801 IOTP/1.0 April 2000

5.3 Data Privacy

 Privacy of information is provided by sending IOTP Messages between
 the various Trading Roles using a secure channel such as [SSL/TLS].
 Use of a secure channel within IOTP is optional.

5.4 Payment Protocol Security

 IOTP is designed to be completely blind to the payment protocol being
 used to effect a payment. From the security perspective, this means
 that IOTP neither helps, nor hinders, the achievement of payment
 security.
 If it is necessary to consider payment security from an IOTP
 perspective, then this should be included in the payment protocol
 supplement which describes how IOTP supports that payment protocol.
 However what IOTP is designed to do is to use digital signatures to
 bind together the record, contained in a "response" message, of each
 trading exchange in a transaction. For example IOTP can bind
 together: an Offer, a Payment and a Delivery.

6. Digital Signatures and IOTP

 IOTP can work successfully without using any digital signatures
 although in an open networking environment it will be less secure -
 see 5.  Security Considerations for a description of the factors that
 need to be considered.
 However, this section describes how to use digital signatures in the
 many situations when they will be needed. Topics covered are:
 o  an overview of how IOTP uses digital signatures
 o  how to check a signature is correctly calculated
 o  how Payment Handlers and Delivery Handlers check they can carry
    out payments or deliveries on behalf of a Merchant.

6.1 How IOTP uses Digital Signatures

 In general, signatures when used with IOTP:
 o  are always treated as IOTP Components (see section 7)
 o  contain digests of one or more IOTP Components or Trading Blocks,
    possibly including other Signature Components, in any IOTP message
    within the same IOTP Transaction

Burdett Informational [Page 77] RFC 2801 IOTP/1.0 April 2000

 o  identify:
  1. which Organisation signed (originated) the signature, and
  1. which Organisation(s) should process the signature in order to

check that the Action the Organisation should take can occur.

 Digital certificates may be associated with digital signatures if
 asymmetric cryptography is being used. However if symmetric
 cryptography is being used, then the digital certificate will be
 replaced by some identifier of the secret key to use.

Burdett Informational [Page 78] RFC 2801 IOTP/1.0 April 2000

 The way in which Signatures Components digest one or more elements is
 illustrated in the figure below.

*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*

IOTP MESSAGE SIGNATURE COMPONENT

IOTP Message Signature Id = P1.3

|-Trans Ref Block        digest TransRefBlk   |-Manifest
|  |      ID=P1.1-----------------------------|->|-Digest of P1.1--
|  |-Trans Id Comp       digest TransIdComp   |  |                 |
|  |     ID = M1.2----------------------------|->|-Digest of M1.2--|
|  |-Msg Id Comp.           digest Signature  |  |                 |
|  |      ID = P1          -------------------|->|-Digest of M1.5--|
|                         |   digest element  |  |                 |
|-Signatures Block        |  -----------------|->|-Digest of M1.7--|
|  |       ID=P1.2        | |  digest element |  |                 |
|  |-Signature ID=P1.3    | |  ---------------|->|-Digest of C1.4--|
|  |-Signature ID=M1.5----  | |               |  |                 |
|  |-Signature ID=P1.4      | | Points to     |   -RecipientInfo*  |
|  |-Certificate ID=M1.6<---|-|---------------|------CertRef=M1.6  |
|  |                        | | Certs to use  |  Sig.ValueRef=P1.4 |
|  |                        | |               |        |           |
|  |                        | |               |        |           |
|-Trading Block. ID=P1.5    | |               |        v           |
|  |-Comp. ID=M1.7----------  |                -Value* ID=P1.4:    |
|  |                          |                   JtvwpMdmSfMbhK<--
|  |-Comp. ID=P1.6            |                   r1Ln3vovbMQttbBI
|  |                          |                   J8pxLjoSRfe1o6k
|  |-Comp. ID=C1.4------------                    OGG7nTFzTi+/0<-
|  |-Comp. ID=C1.5
                           Digital signature of Manifest element
                           using certificate identified by CertRef
 Elements that are digested can be in any IOTP Message
      within the same IOTP Transaction

*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*

                       Figure 10 Signature Digests

Burdett Informational [Page 79] RFC 2801 IOTP/1.0 April 2000

 Note: The classic example of one signature signing another in IOTP,
 is when an Offer is first signed by a Merchant creating an "Offer
 Response" signature, which is then later signed by a Payment Handler
 together with a record of the payment creating a "Payment Receipt"
 signature. In this way, the payment in an IOTP Transaction is bound
 to the Merchant's offer.
 Note that one Manifest may be associated with multiple signature
 "Value" elements where each Value element contains a digital
 signature over the same Manifest, perhaps using the same (or
 different) signature algorithm but using a different certificate or
 shared secret key. Specifically it will allow the Merchant to agree
 on different shared secrets keys with their Payment Handler and
 Delivery Handler.
 The detailed definitions of a Signature component are contained in
 section 7.19.
 The remainder of this section contains:
 o  an example of how IOTP uses signatures
 o  how the OriginatorInfo and RecipientInfo elements within a
    Signature Component are used to identify the Organisations
    associated with the signature
 o  how IOTP uses signatures to prove actions complete successfully

6.1.1 IOTP Signature Example

 An example of how signatures are used is illustrated in the figure
 below which shows how the various components and elements in a
 Baseline Purchase relate to one another. Refer to this example in the
 later description of how signatures are used to check a payment or
 delivery can occur (see section 6.3).
 Note: A Baseline Purchase transaction has been used for illustration
 purposes. The usage of the elements and attributes is the same for
 all types of IOTP Transactions.

Burdett Informational [Page 80] RFC 2801 IOTP/1.0 April 2000

*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*

TPO SELECTION BLOCK TPO BLOCK IOTPSIGNATURE BLOCK

                                               | (Offer Response)

Brand Selection Organisation←– |——Signature

 Component                 Component       |   |      Component
    |                       |              |           -Manifest
    |BrandList               -Trading Role |            |
    |  Ref                     Element     | Originator |-Orig.
    v                         (Merchant)    ------------|--Info
  Brand List                                    Ref     |
>Component                                              |

| |-Protocol ——> Organisation Recipient |-Recipient | | Amount Elem | Component ←—————–|–Info | | | | | Refs | | |Pay|Protocol |Action -Trading Role | | | | Ref |OrgRef Element | | | v | (Payment Handler) | | -PayProtocol– | | Elem →Organisation Recipient |-Recipient | | Component ←——————-Info | | | Refs | | -Trading Role | | Element | | (Delivery Handler | | OFFER RESPONSE BLOCK | | |BrandListRef |ActionOrgRef | |

  1. -Payment —Delivery

Component Component

The Manifest element in the Signature Component contains digests of: the Trans Ref Block (not shown); the Transaction ID Component (not shown); Organisation Components (Merchant, Payment Handler, Delivery Handler); the Brand List Component; the Order Component, the Payment Component the Delivery Component and the Brand Selection Component (if a Brand Dependent Purchase).

*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*

       Figure 11 Example use of Signatures for Baseline Purchase

Burdett Informational [Page 81] RFC 2801 IOTP/1.0 April 2000

6.1.2 OriginatorInfo and RecipientInfo Elements

 The OriginatorRef attribute of the OriginatorInfo element in the
 Signature Component contains an Element Reference (see section 3.5)
 that points to the Organisation Component of the Organisation which
 generated the Signature. In this example its the Merchant.
 Note that the value of the content of the Attribute element with a
 Type attribute set to IOTP Signature Type must match the Trading Role
 of the Organisation which signed it. If it does not, then it is an
 error. Valid combinations are given in the table below.
       IOTP Signature Type    Valid Trading Role
       OfferResponse           Merchant
       PaymentResponse         PaymentHandler
       DeliveryResponse        DeliveryHandler
       AuthenticationRequest   any role
       AuthenticationResponse  any role
       PingRequest             any role
       PingResponse            any role
 The RecipientRefs attribute of the RecipientInfo element in the
 Signature Component contains Element References to the Organisation
 Components of the Organisations that should use the signature to
 verify that:
 o  they have a pre-existing relationship with the Organisation that
    generated the signature,
 o  the data which is secured by the signature has not been changed,
 o  the data has been signed correctly, and
 o  the action they are required to undertake on behalf of the
    Merchant is therefore authorised.
 Note that if symmetric cryptography is being used then a separate
 RecipientInfo and Value elements for each different set of shared
 secret keys are likely within the Signature Component.

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 Alternatively if asymmetric cryptography is being used then the
 RecpientRefs attribute of one RecipientInfo element may refer to
 multiple Organisation Components if they are all using the same
 certificates.

6.1.3 Using signatures to Prove Actions Complete Successfully

 Proving an action completed successfully, is achieved by signing data
 on Response messages. Specifically:
 o  on the Offer Response, when a Merchant is making an Offer to the
    Consumer which can then be sent to either:
  1. a Payment Handler to prove that the Merchant authorises

Payment, or

  1. a Delivery Handler to prove that Merchant authorises Delivery,

provided other necessary authorisations are complete (see

       below)
 o  on the Payment Response, when a Payment Handler is generating a
    Payment Receipt which can be sent to either:
  1. a Delivery Handler, in a Delivery Request Block to authorise

Delivery together with the Offer Response signature, or

  1. another Payment Handler, in a second Payment Request, to

authorise the second payment in a Value Exchange IOTP

       Transaction
 o  Delivery Response, when a Delivery Handler is generating a
    Delivery Note. This can be used to prove after the event what the
    Delivery Handler said they would do
 o  Authentication Response. One method of authenticating another
    party to a trade is to send an Authentication Request specifying
    that a Digital Signature should be used for authentication
 o  Transaction Status Inquiry. The Inquiry Response Block may be
    digitally signed to attest to the authenticity of the response
 o  Ping. The Ping Response may be digitally signed so that checks can
    be made that the signature can be understood.
 This proof of an action may, in future versions of IOTP, also be used
 to prove after the event that the IOTP transaction occurred. For
 example to a Customer Care Provider.

Burdett Informational [Page 83] RFC 2801 IOTP/1.0 April 2000

6.2 Checking a Signature is Correctly Calculated

 Checking a signature is correctly calculated is part of checking for
 Message Level Errors (see section 4.3.2). It is included here so that
 all signature and security related considerations are kept together.
 Before a Trading Role can check a signature it must identify which of
 the potentially multiple Signature elements should be checked. The
 steps involved are as follows:
 o  check that a Signature Block is present and it contains one or
    more Signature Components
 o  identify the Organisation Component which contains an OrgId
    attribute for the Organisation which is carrying out the signature
    check. If no or more than one Organisation Component is found then
    it is an error
 o  use the ID attribute of the Organisation Component to find the
    RecipientInfo element that contains a RecipientRefs attribute that
    refers to that Organisation Component. Note there may be no
    signatures to verify
 o  check the Signature Component that contains the identified
    RecipientInfo element as follows:
  1. use the SignatureValueRef and the SignatureAlgorithmRef

attributes to identify, respectively: the Value element that

       contains the signature to be checked and the Signature
       Algorithm element that describes the signature algorithm to be
       used to verify the Signature, then
  1. if the Signature Algorithm element indicates that asymmetric

cryptography is being used then use the SignatureCertRef to

       identify the Certificate to be used by the signature algorithm
  1. if Signature Algorithm element indicates that symmetric

cryptography is being used then the content of the

       RecipientInfo element is used to identify the correct shared
       secret key to use
  1. use the specified signature algorithm to check that the Value

Element correctly signs the Manifest Element

  1. check that the Digest Elements in the Manifest Element are

correctly calculated where Components or Blocks referenced by

       the Digest have been received by the Organisation checking the
       signature.

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6.3 Checking a Payment or Delivery can occur

 This section describes the processes required for a Payment Handler
 or Delivery Handler to check that a payment or delivery can occur.
 This may include checking signatures if this is specified by the
 Merchant.
 In outline the steps are:
 o  check that the Payment Request or Delivery Request has been sent
    to the correct Organisation
 o  check that correct IOTP components are present in the request, and
 o  check that the payment or delivery is authorised
 For clarity and brevity the following terms or phrases are used in
 this section:
 o  a "Request Block" is used to refer to either a Payment Request
    Block (see section 8.7) or a Delivery Request Block (see section
    8.10) unless specified to the contrary
 o  a "Response Block" is used to refer to either a Payment Response
    Block (see section 8.9) or a Delivery Response Block (see section
    8.11)
 o  an "Action" is used to refer to an action which occurs on receipt
    of a Request Block. Actions can be either a Payment or a Delivery
 o  an "Action Organisation", is used to refer to the Payment Handler
    or Delivery Handler that carries out an Action
 o  a "Signer of an Action", is used to refer to the Organisations
    that sign data about an Action to authorise the Action, either in
    whole or in part
 o  a "Verifier of an Action", is used to refer to the Organisations
    that verify data to determine if they are authorised to carry out
    the Action
 o  an ActionOrgRef attribute contains Element References which can be
    used to identify the "Action Organisation" that should carry out
    an Action

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6.3.1 Check Request Block sent Correct Organisation

 Checking the Request Block was sent to the correct Organisation
 varies depending on whether the request refers to a Payment or a
 Delivery.

6.3.1.1 Payment

 In outline a Payment Handler checks if it can accept or make a
 payment by identifying the Payment Component in the Payment Request
 Block it has received, then using the ID of the Payment Component to
 track through the Brand List and Brand Selection Components to
 identify the Organisation selected by the Consumer and then checking
 that this Organisation is itself.

Burdett Informational [Page 86] RFC 2801 IOTP/1.0 April 2000

 The way data is accessed to do this is illustrated in the figure
 below.
  • +*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*

Start

                                                    |
                                                    v
 Brand List<--------------------------+-----------Payment
 Component         BrandListRef       |          Component
  |                                   |
  |-Brand<--------------------------  |
  | Element        BrandRef         | |
  |  |                          Brand Selection
  |  |Protocol                     Component
  |  | AmountRefs                   | |
  |  v                  Protocol    | |
  |-Protocol Amount<----------------  |
  | Element----------  AmountRef      |
  |  |               |                |
  |  |Currency       |Pay             |
  |  | AmountRefs    |Protocol        |
  |  v               |Ref             |
  |-Currency Amount  |                |
  | Element<---------|----------------
  |                  |
   -PayProtocol<-----
    Element---------------------->Organisation
                   Action         Component
                   OrgRef          |
                                    -Trading Role
                                      Element
                                   (Payment Handler)
  • -*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*
    Figure 12 Checking a Payment Handler can carry out a Payment
 The following describes the steps involved and the checks which need
 to be made:
 o  Identify the Payment Component (see section 7.9) in the Payment
    Request Block that was received.
 o  Identify the Brand List and Brand Selection Components for the
    Payment Component. This involves:

Burdett Informational [Page 87] RFC 2801 IOTP/1.0 April 2000

  1. identifying the Brand List Component (see section 7.7) where

the value of its ID attribute matches the BrandListRef

       attribute of the Payment Component. If no or more than one
       Brand List Component is found there is an error.
  1. identifying the Brand Selection Component (see section 7.8)

where the value of its BrandListRef attribute matches the

       BrandListRef of the Payment Component. If no or more than one
       matching Brand Selection Component is found there is an error.
 o  Identify the Brand, Protocol Amount, Pay Protocol and Currency
    Amount elements within the Brand List that have been selected by
    the Consumer as follows:
  1. the Brand Element (see section 7.7.1) selected is the element

where the value of its Id attribute matches the value of the

       BrandRef attribute in the Brand Selection. If no or more than
       one matching Brand Element is found then there is an error.
  1. the Protocol Amount Element (see section 7.7.3) selected is the

element where the value of its Id attribute matches the value

       of the ProtocolAmountRef attribute in the Brand Selection
       Component. If no or more than one matching Protocol Amount
       Element is found there is an error
  1. the Pay Protocol Element (see section 7.7.5) selected is the

element where the value of its Id attribute matches the value

       of the PayProtocolRef attribute in the identified Protocol
       Amount Element.  If no or more than one matching Pay Protocol
       Element is found there is an error
  1. the Currency Amount Element (see section 7.7.4) selected is the

element where the value of its Id attribute matches the value

       of the CurrencyAmountRef attribute in the Brand Selection
       Component. If no or more than one matching Currency Amount
       element is found there is an error
 o  Check the consistency of the references in the Brand List and
    Brand Selection Components:
  1. check that an Element Reference exists in the

ProtocolAmountRefs attribute of the identified Brand Element

       that matches the Id attribute of the identified Protocol Amount
       Element. If no or more than one matching Element Reference can
       be found there is an error

Burdett Informational [Page 88] RFC 2801 IOTP/1.0 April 2000

  1. check that the CurrencyAmountRefs attribute of the identified

Protocol Amount element contains an element reference that

       matches the Id attribute of the identified Currency Amount
       element. If no or more than one matching Element Reference is
       found there is an error.
  1. check the consistency of the elements in the Brand List.

Specifically, the selected Brand, Protocol Amount, Pay Protocol

       and Currency Amount Elements are all child elements of the
       identified Brand List Component. If they are not there is an
       error.
 o  Check that the Payment Handler that received the Payment Request
    Block is the Payment Handler selected by the Consumer. This
    involves:
  1. identifying the Organisation Component for the Payment Handler.

This is the Organisation Component where its ID attribute

       matches the ActionOrgRef attribute in the identified Pay
       Protocol Element. If no or more than one matching Organisation
       Component is found there is an error
  1. checking the Organisation Component has a Trading Role Element

with a Role attribute of PaymentHandler. If not there is an

       error
  1. finally, if the identified Organisation Component is not the

same as the Organisation that received the Payment Request

       Block, then there is an error.

Burdett Informational [Page 89] RFC 2801 IOTP/1.0 April 2000

6.3.1.2 Delivery

 The way data is accessed by a Delivery Handler in order to check that
 it may carry out a delivery is illustrated in the figure below.
  • +*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*

Start

                            |
                            v
                         Delivery
                         Component
                            |
                            |ActionOrgRef
                            |
                            v
                         Organisation
                         Component
                         |
                          -Trading Role
                            Element
                         (Delivery Handler)
  • -*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*
       Figure 13 Checking a Delivery Handler can carry out a Delivery
 The steps involved are as follows:
 o  Identify the Delivery Component in the Delivery Request Block. If
    there is no or more than one matching Delivery Component there is
    an error
 o  Use the ActionOrgRef attribute of the Delivery Component to
    identify the Organisation Component of the Delivery Handler. If
    there is no or more than one matching Organisation Component there
    is an error
 o  If the Organisation Component for the Delivery Handler does not
    have a Trading Role Element with a Role attribute of
    DeliveryHandler there is an error
 o  Finally, if the Organisation that received the Delivery Request
    Block does not identify the Organisation Component for the
    Delivery Handler as itself, then there is an error.

Burdett Informational [Page 90] RFC 2801 IOTP/1.0 April 2000

6.3.2 Check Correct Components present in Request Block

 Check that the correct components are present in the Payment Request
 Block (see section 8.7) or in the Delivery Request Block (see section
 8.10).
 If components are missing, there is an error.

6.3.3 Check an Action is Authorised

 The previous steps identified the Action Organisation and that all
 the necessary components are present. This step checks that the
 Action Organisation is authorised to carry out the Action.
 In outline the Action Organisation will identifies the Merchant,
 checks that it has a pre-existing agreement with the Merchant that
 allows it carry out the Action and that any constraints implied by
 that agreement are being followed, then, if signatures are required,
 it checks that they sign the correct data.
 The steps involved are as follows:
 o  Identify the Merchant. This is the Organisation Component with a
    Trading Role Element which has a Role attribute with a value of
    Merchant. If no or more than one Trading Role Element is found,
    there is an error
 o  Check the Action Organisation's agreements with the Merchant
    allows the Action to be carried out. To do this the Action
    Organisation must check that:
  1. the Merchant is known and a pre-existing agreement exists for

the Action Organisation to be their agent for the payment or

       delivery
  1. they are allowed to take part in the type of IOTP transaction

that is occurring. For example a Payment Handler may have

       agreed to accept payments as part of a Baseline Purchase, but
       not make payments as part of a Baseline Refund
  1. any constraints in their agreement with the Merchant are being

followed, for example, whether or not an Offer Response

       signature is required
 o  Check the signatures are correct. If signatures are required then
    they need to be checked. This involves:

Burdett Informational [Page 91] RFC 2801 IOTP/1.0 April 2000

  1. Identifying the correct signatures to check. This involves the

Action Organisation identifying the Signature Components that

       contain references to the Action Organisation (see 6.3.1).
       Depending on the IOTP Transaction being carried out (see
       section 9) either one or two signatures may be identified
  1. checking that the Signature Components are correct. This

involves checking that Digest elements exist within the

       Manifest Element that refer to the necessary Trading Components
       (see section 6.3.3.1).

6.3.3.1 Check the Signatures Digests are correct

 All Signature Components contained within IOTP Messages must include
 Digest elements that refer to:
 o  the Transaction Id Component (see section 3.3.1) of the IOTP
    message that contains the Signature Component. This binds the
    globally unique IotpTransId to other components which make up the
    IOTP Transaction
 o  the Transaction Reference Block (see section 3.3) of the first
    IOTP Message that contained the signature. This binds the
    IotpTransId with information about the IOTP Message contained
    inside the Message Id Component (see section 3.3.2).
 Check that each Signature Component contains Digest elements that
 refer to the correct data required.
 The Digest elements that need to be present depend on the Trading
 Role of the Organisation which generated (signed) the signature:
 o  if the signer of the signature is a Merchant then:
  1. Digest elements must be present for all the components in the

Request Block apart from the Brand Selection Component which is

       optional
 o  if the signer of the signature is a Payment Handler then Digest
    elements must be present for:
  1. the Signature Component signed by the Merchant, and optionally
  1. one or more Signature Components signed by the previous Payment

Handler(s) in the Transaction.

Burdett Informational [Page 92] RFC 2801 IOTP/1.0 April 2000

7. Trading Components

 This section describes the Trading Components used within IOTP.
 Trading Components are the child XML elements which occur immediately
 below a Trading Block as illustrated in the diagram below.

Burdett Informational [Page 93] RFC 2801 IOTP/1.0 April 2000

  • +*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*
           IOTP MESSAGE  <----------- IOTP Message - an XML Document
            |                         which is transported between the
            |                         Trading Roles
            |-Trans Ref Block <-----  Trans Ref Block - contains
            |  |                      information which describes the
            |  |                      IOTP Transaction and the IOTP
                                      Message.
  --------> |  |-Trans Id Comp. <---  Transaction Id Component -
 |          |  |                      uniquely identifies the IOTP
 |          |  |                      Transaction. The Trans Id
 |          |  |                      Components are the same across
 |          |  |                      all IOTP messages that comprise
 |          |  |                      a single IOTP transaction.
 |          |  |-Msg Id Comp. <-----  Message Id Component -
 |          |                         identifies and describes an IOTP
 |          |                         Message within an IOTP
 |          |                         Transaction
 |          |-Signature Block <-----  Signature Block (optional) -
 |          |  |                      contains one or more Signature
 |          |  |                      Components and their associated
 |          |  |                      Certificates
 |     ---> |  |-Signature Comp. <--  Signature Component - contains
 |    |     |  |                      digital signatures. Signatures
 |    |     |  |                      may sign digests of the Trans Ref
 |    |     |  |                      Block and any Trading Component
 |    |     |  |                      in any IOTP Message in the same
 |    |     |  |                      IOTP Transaction.
 |    |     |  |-Certificate Comp. <- Certificate Component. Used to
 |    |     |                         check the signature.
   Trading  |-Trading Block <-------- Trading Block - an XML Element
 Components |  |-Trading Comp.        within an IOTP Message that
 |    |     |  |-Trading Comp.        contains a predefined set of
 |     ---> |  |-Trading Comp.        Trading Components
 |          |  |-Trading Comp.
 |          |  |-Trading Comp. <----- Trading Components - XML
 |          |                         Elements within a Trading Block
 |          |-Trading Block           that contain a predefined set of
  --------> |  |-Trading Comp.        XML elements and attributes
            |  |-Trading Comp.        containing information required
            |  |-Trading Comp.        to support a Trading Exchange
            |  |-Trading Comp.
            |  |-Trading Comp.
 *-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*
                        Figure 14 Trading Components

Burdett Informational [Page 94] RFC 2801 IOTP/1.0 April 2000

 The Trading Components described in this section are listed below in
 approximately the sequence they are likely to be used:
 o  Protocol Options Component
 o  Authentication Request Component
 o  Authentication Response Component
 o  Trading Role Information Request Component
 o  Order Component
 o  Organisation Component
 o  Brand List Component
 o  Brand Selection Component
 o  Payment Component
 o  Payment Scheme Component
 o  Payment Receipt Component
 o  Delivery Component
 o  Delivery Data Component
 o  Delivery Note Component
 o  Signature Component
 o  Certificate Component
 o  Error Component
 Note that the following components are listed in other sections of
 this specification:
 o  Transaction Id Component (see section 3.3.1)
 o  Message Id Component (see section 3.3.2)

Burdett Informational [Page 95] RFC 2801 IOTP/1.0 April 2000

7.1 Protocol Options Component

 Protocol options are options which apply to the IOTP Transaction as a
 whole. Essentially it provides a short description of the entire
 transaction and the net location which the Consumer role should
 branch to if the IOTP Transaction is successful.
 The definition of a Protocol Options Component is as follows.
 <!ELEMENT ProtocolOptions EMPTY >
 <!ATTLIST ProtocolOptions
  ID                 ID      #REQUIRED
  xml:lang           NMTOKEN #REQUIRED
  ShortDesc          CDATA   #REQUIRED
  SenderNetLocn      CDATA   #IMPLIED
  SecureSenderNetLocn CDATA  #IMPLIED
  SuccessNetLocn     CDATA   #REQUIRED >
 Attributes:
 ID                   An identifier which uniquely identifies the
                      Protocol Options Component within the IOTP
                      Transaction.
 Xml:lang             Defines the language used by attributes or child
                      elements within this component, unless
                      overridden by an xml:lang attribute on a child
                      element. See section 3.8 Identifying Languages.
 ShortDesc            This contains a short description of the IOTP
                      Transaction in the language defined by xml:lang.
                      Its purpose is to provide an explanation of what
                      type of IOTP Transaction is being conducted by
                      the parties involved.
                      It is used to facilitate selecting an individual
                      transaction from a list of similar transactions,
                      for example from a database of IOTP transactions
                      which has been stored by a Consumer, Merchant,
                      etc.
 SenderNetLocn        This contains the non secured net location of
                      the sender of the TPO Block in which the
                      Protocol Options Component is contained.
                      It is the net location to which the recipient of
                      the TPO block should send a TPO Selection Block
                      if required.

Burdett Informational [Page 96] RFC 2801 IOTP/1.0 April 2000

                      The content of this attribute is dependent on
                      the Transport Mechanism see the Transport
                      Mechanism Supplement.
 SecureSenderNetLocn  This contains the secured net location of the
                      sender of the TPO Block in which the Protocol
                      Options Component is contained.
                      The content of this attribute is dependent on
                      the Transport Mechanism see the Transport
                      Mechanism Supplement.
 SuccessNetLocn       This contains the net location that should be
                      displayed after the IOTP Transaction has
                      successfully completed.
                      The content of this attribute is dependent on
                      the Transport Mechanism see the Transport
                      Mechanism Supplement.
 Either SenderNetLocn, SecureSenderNetLocn or both must be present.

7.2 Authentication Request Component

 This Trading Component contains parameter data that is used in an
 Authentication of one Trading Role by another. Its definition is as
 follows.
 <!ELEMENT AuthReq (Algorithm, PackagedContent*)>
 <!ATTLIST AuthReq
  ID                 ID      #REQUIRED
  AuthenticationId   CDATA   #REQUIRED
  ContentSoftwareId  CDATA   #IMPLIED >
 If required the Algorithm may use the challenge data, contained in
 the Packaged Content elements within the Authentication Request
 Component in its calculation. The format of the Packaged Contents are
 Algorithm dependent.
 Attributes:
 ID                 An identifier which uniquely identifies the
                    Authentication Request Component within the IOTP
                    Transaction.
 AuthenticationId   An identifier specified by the Authenticator
                    which, if returned by the Organisation that
                    receives the Authentication Request, will enable

Burdett Informational [Page 97] RFC 2801 IOTP/1.0 April 2000

                    the Authenticator to identify which Authentication
                    is being referred to.
 ContentSoftwareId  See section 14.Glossary
 Content:
 PackagedContent    This contains the challenge data as one or more
                    Packaged Content (see section 3.7) that is to be
                    responded to using the Algorithm defined by the
                    Algorithm element.
 Algorithm          This contains information which describes the
                    Algorithm (see 7.19 Signature Components) that
                    must be used to generate the Authentication
                    Response.
                    The Algorithms that may be used are identified by
                    the Name attribute of the Algorithm element. For
                    valid values see section 12. IANA Considerations.

7.3 Authentication Response Component

 The Authentication Response Component contains the results of an
 authentication request.  It uses the Algorithm contained in the
 Authentication Request Component (see section 7.2) selected from the
 Authentication Request Block (see section 8.4).
 Depending on the Algorithm selected, the results of applying the
 algorithm will either be contained in a Signature Component that
 signs both the Authentication Response and potentially other data, or
 in the Packaged Content elements within the Authentication Response
 Component.  Its definition is as follows.
 <!ELEMENT AuthResp (PackagedContent*) >
 <!ATTLIST AuthResp
  ID                 ID      #REQUIRED
  AuthenticationId   CDATA   #REQUIRED
  SelectedAlgorithmRef NMTOKEN #REQUIRED
  ContentSoftwareId  CDATA   #IMPLIED >
 Attributes:
 ID                     An identifier which uniquely identifies the
                        Authentication Response Component within the
                        IOTP Transaction.

Burdett Informational [Page 98] RFC 2801 IOTP/1.0 April 2000

 AuthenticationId       The Authentication identifier specified by the
                        Authenticator that was included in the
                        Authentication Request Component(see section
                        7.2). This will enable the Authenticator to
                        identify the Authentication that is being
                        referred to.
 SelectedAlgorithmRef   An Element Reference that identifies the
                        Algorithm element used to generate the
                        Authentication Response.
 ContentSoftwareId      See section 14.Glossary.
 Content:
 PackagedContent    This may contain the response generated as a
                    result of applying the Algorithm selected from the
                    Authentication Request Component see section 7.2.
                    For example, for a payment specific scheme, it may
                    contain scheme-specific data. Refer to the scheme-
                    specific supplemental documentation for
                    definitions of its content.

7.4 Trading Role Information Request Component

 This Trading Component contains a list of Trading Roles (see section
 2.1) about which information is being requested. The result of a
 Trading Role Request is a set of Organisation Components (see section
 7.6) that describe each of the Trading Roles requested.
 Example usage includes:
 o  a Merchant requesting that a Consumer provides Organisation
    Components for the Consumer and DelivTo Trading Roles
 o  a Consumer requesting from a Merchant, information about the
    Payment Handlers and Delivery Handlers that the Merchant uses.
 Its definition is as follows.
 <!ELEMENT TradingRoleInfoReq EMPTY>
 <!ATTLIST TradingRoleInfoReq
  ID                 ID      #REQUIRED
  TradingRoleList    NMTOKENS #REQUIRED >

Burdett Informational [Page 99] RFC 2801 IOTP/1.0 April 2000

 Attributes:
 ID                 An identifier which uniquely identifies the
                    Trading Role Information Request Component within
                    the IOTP Transaction.
 TradingRoleList    Contains a list of one or more Trading Roles (see
                    the TradingRole attribute of the Trading Role
                    Element - section 7.6.2) for which information is
                    being requested.

7.5 Order Component

 An Order Component contains information about an order. Its
 definition is as follows.
 <!ELEMENT Order (PackagedContent*) >
 <!ATTLIST Order
  ID                 ID      #REQUIRED
  xml:lang           NMTOKEN #REQUIRED
  OrderIdentifier    CDATA   #REQUIRED
  ShortDesc          CDATA   #REQUIRED
  OkFrom             CDATA   #REQUIRED
  OkTo               CDATA   #REQUIRED
  ApplicableLaw      CDATA   #REQUIRED
  ContentSoftwareId  CDATA   #IMPLIED >
 Attributes:
 ID                 An identifier which uniquely identifies the Order
                    Component within the IOTP Transaction.
 xml:lang           Defines the language used by attributes or child
                    elements within this component, unless overridden
                    by an xml:lang attribute on a child element. See
                    section 3.8 Identifying Languages.
 OrderIdentifier    This is a code, reference number or other
                    identifier which the creator of the Order may use
                    to identify the order. It must be unique within an
                    IOTP Transaction. If it is used in this way, then
                    it may remove the need to specify any content for
                    the Order element as the reference can be used to
                    look up the necessary information in a database.
 ShortDesc          A short description of the order in the language
                    defined by xml:lang. It is used to facilitate
                    selecting an individual order from a list of

Burdett Informational [Page 100] RFC 2801 IOTP/1.0 April 2000

                    orders, for example from a database of orders
                    which has been stored by a Consumer, Merchant,
                    etc.
 OkFrom             The date and time in [UTC] format after which the
                    offer made by the Merchant lapses.
 OkTo               The date and time in [UTC] format before which a
                    Value Acquirer may accept the offer made by the
                    Merchant is not valid.
 ApplicableLaw      A phrase in the language defined by xml:lang which
                    describes the state or country of jurisdiction
                    which will apply in resolving problems or
                    disputes.
 ContentSoftwareId  See section 14.Glossary.
 Content:
 PackagedContent    An optional description of the order information
                    as one or more Packaged Contents (see section
                    3.7).

7.5.1 Order Description Content

 The Packaged Content element will normally be required, however it
 may be omitted where sufficient information about the purchase can be
 provided in the ShortDesc attribute. If the full Order Description
 requires it several Packaged Content elements may be used.
 Although the amount and currency are likely to appear in the Packaged
 Content of the Order Description it is the amount and currency
 contained in the payment related trading components (Brand List,
 Brand Selection and Payment) that is authoritative. This means it is
 important that the amount actually being paid (as contained in the
 payment related trading components) is prominently displayed to the
 Consumer.
 For interoperability, implementations must support Plain Text, HTML
 and XML as a minimum so that it can be easily displayed.

7.5.2 OkFrom and OkTo Timestamps

 Note that:
 o  the OkFrom date may be later than the OkFrom date on the Payment
    Component (see section 7.9) associated with this order, and

Burdett Informational [Page 101] RFC 2801 IOTP/1.0 April 2000

 o  similarly, the OkTo date may be earlier that the OkTo date on the
    Payment Component (see section 7.9).
 Note: Disclaimer. The following information provided in this note
 does not represent formal advice of any of the authors of this
 specification. Readers of this specification must form their own
 views and seek their own legal counsel on the usefulness and
 applicability of this information.
 The merchant in the context of Internet commerce with anonymous
 consumers initially frames the terms of the offer on the web page,
 and in order to obtain the goods or services, the consumer must
 accept them.
 If there is to be a time-limited offer, it is recommended that
 merchants communicate this to the consumer and state in the order
 description in a manner which is clear to the consumer that:
 o  the offer is time limited
 o  the OkFrom and OkTo timestamps specify the validity of the offer
 o  the clock, e.g., the merchant's clock, that will be used to
    determine the validity of the offer
 Also note that although the OkFrom and OkTo dates are likely to
 appear in the Packaged Content of the Order Description it is the
 dates contained in the Order Component that is authoritative. This
 means it is important that the OkFrom and OkTo dates actually being
 used is prominently displayed to the Consumer.

7.6 Organisation Component

 The Organisation Component provides information about an individual
 or an Organisation. This can be used for a variety of purposes. For
 example:
 o to describe the merchant who is selling the goods,
 o to identify who made a purchase,
 o to identify who will take delivery of goods,
 o to provide a customer care contact,
 o to describe who will be the Payment Handler.

Burdett Informational [Page 102] RFC 2801 IOTP/1.0 April 2000

 Note that the Organisation Components which must be present in an
 IOTP Message are dependent on the particular transaction being
 carried out.  Refer to section 9. Internet Open Trading Protocol
 Transactions, for more details.
 Its definition is as follows.
 <!ELEMENT Org (TradingRole+, ContactInfo?,
      PersonName?, PostalAddress?)>
 <!ATTLIST Org
  ID                 ID      #REQUIRED
  xml:lang           NMTOKEN #REQUIRED
  OrgId              CDATA   #REQUIRED
  LegalName          CDATA   #IMPLIED
  ShortDesc          CDATA   #IMPLIED
  LogoNetLocn        CDATA   #IMPLIED >
 Attributes:
 ID                 An identifier which uniquely identifies the
                    Organisation Component within the IOTP
                    Transaction.
 xml:lang           Defines the language used by attributes or child
                    elements within this component, unless overridden
                    by an xml:lang attribute on a child element. See
                    section 3.8 Identifying Languages.
 OrgId              A code which identifies the Organisation described
                    by the Organisation Component. See 7.6.1
                    Organisation IDs, below.
 LegalName          For Organisations which are companies this is
                    their legal name in the language defined by
                    xml:lang. It is required for Organisations who
                    have a Trading Role other than Consumer or
                    DelivTo.
 ShortDesc          A short description of the Organisation in the
                    language defined by xml:lang. It is typically the
                    name by which the Organisation is commonly known.
                    For example, if the legal name was "Blue Meadows
                    Financial Services Inc.". Then its short name
                    would likely be "Blue Meadows".
                    It is used to facilitate selecting an individual
                    Organisation from a list of Organisations, for
                    example from a database of Organisations involved

Burdett Informational [Page 103] RFC 2801 IOTP/1.0 April 2000

                    in IOTP Transactions which has been stored by a
                    consumer.
 LogoNetLocn        The net location which can be used to download the
                    logo for the Organisation.
                    See section 10 Retrieving Logos.
                    The content of this attribute must conform to
                    [RFC1738].
 Content:
 TradingRole        See 7.6.2 Trading Role Element below.
 ContactInfo        See 7.6.3 Contact Information Element below.
 PersonName         See 7.6.4 Person Name below.
 PostalAddress      See 7.6.5 Postal Address below.

7.6.1 Organisation IDs

 Organisation IDs are used by one IOTP Trading Role to identify
 another.  In order to avoid confusion, this means that these IDs must
 be globally unique.
 In principle this is achieved in the following way:
 o  the Organisation Id for all trading roles, apart from the Consumer
    Trading Role, uses a domain name as their globally unique
    identifier,
 o  the Organisation Id for a Consumer Trading Role is allocated by
    one of the other Trading Roles in an IOTP Transaction and is made
    unique by concatenating it with that other roles' Organisation Id,
 o  once a Consumer is allocated an Organisation Id within an IOTP
    Transaction the same Organisation Id is used by all the other
    trading roles in that IOTP transaction to identify that Consumer.
 Specifically, the content of the Organisation ID is defined as
 follows:
 OrgId ::= NonConsumerOrgId | ConsumerOrgId
 NonConsumerOrgId ::= DomainName
 ConsumerOrgId ::= ConsumerOrgIdPrefix (namechar)+ "/" NonConsumerOrgId
 ConsumerOrgIdPrefix ::= "Consumer:"

Burdett Informational [Page 104] RFC 2801 IOTP/1.0 April 2000

 ConsumerOrgId      The Organisation ID for a Consumer consists of:
                     o a standard prefix to identify that the
                       Organisation Id is for a consumer, followed by
                     o one or more characters which conform to the
                       definition of an XML "namechar". See [XML]
                       specifications, followed by
                     o the NonConsumerOrgId for the Organisation
                       which allocated the ConsumerOrgId. It is
                       normally the Merchant role.
                    Use of upper and lower case is not significant.
 NonConsumerOrgId   If the Role is not Consumer then this contains the
                    Canonical Name for the non-consumer Organisation
                    being described by the Organisation Component. See
                    [DNS] optionally followed by additional
                    characters, if required, to make the
                    NonConsumerOrgId unique.
                    Note that a NonConsumerOrgId may not start with
                    the ConsumerOrgIdPrefix.
                    Use of upper and lower case is not significant.
 Examples of Organisation Ids follow:
 o  newjerseybooks.com - a merchant Organisation id
 o  westernbank.co.uk - a Payment Handler Organisation id
 o  consumer:1000247ABH/newjerseybooks.com - a consumer Organisation
    id allocated by a merchant

7.6.2 Trading Role Element

 This identifies the Trading Role of an individual or Organisation in
 the IOTP Transaction. Note, an Organisation may have more than one
 Trading Role and several roles may be present in one Organisation
 element. Its definition is as follows:
 <!ELEMENT TradingRole EMPTY >
 <!ATTLIST TradingRole
  ID                 ID      #REQUIRED
  TradingRole        NMTOKEN #REQUIRED
  IotpMsgIdPrefix    NMTOKEN #REQUIRED
  CancelNetLocn      CDATA   #IMPLIED
  ErrorNetLocn       CDATA   #IMPLIED

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  ErrorLogNetLocn    CDATA   #IMPLIED >
 Attributes:
 ID                 An identifier which uniquely identifies the
                    Trading Role Element within the IOTP Transaction.
 TradingRole        The trading role of the Organisation. Valid values
                    are:
                     o Consumer. The person or Organisation that is
                       acting in the role of a consumer in the IOTP
                       Transaction.
                     o Merchant. The person or Organisation that is
                       acting in the role of merchant in the IOTP
                       Transaction.
                     o PaymentHandler. The financial institution or
                       other Organisation which is a Payment Handler
                       for the IOTP Transaction
                     o DeliveryHandler. The person or Organisation
                       that is the delivering the goods or services
                       for the IOTP Transaction
                     o DelivTo. The person or Organisation that is
                       receiving the delivery of goods or services in
                       the IOTP Transaction
                     o CustCare. The Organisation and/or individual
                       who will provide customer care for an IOTP
                       Transaction.
                    Values of TradingRole are controlled under the
                    procedures defined in section 12 IANA
                    Considerations which also allows user defined
                    values to be defined.
 IotpMsgIdPrefix    Contains the prefix which must be used for all
                    IOTP Messages sent by the Trading Role in this
                    IOTP Transaction. The values to be used are
                    defined in 3.4.1 IOTP Message ID Attribute
                    Definition.
 CancelNetLocn      This contains the net location of where the
                    Consumer should go to if the Consumer cancels the
                    transaction for some reason. It can be used by the
                    Trading Role to provide a response which is more
                    tailored to the circumstances of a particular
                    transaction.

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                    This attribute:
                     o must not be present when TradingRole is set to
                       Consumer role or DelivTo,
                     o must be present when TradingRole is set to
                       Merchant, PaymentHandler or DeliveryHandler.
                    The content of this attribute is dependent on the
                    Transport Mechanism see the Transport Mechanism
                    Supplement.
 ErrorNetLocn       This contains the net location that should be
                    displayed by the Consumer after the Consumer has
                    either received or generated an Error Block
                    containing an Error Component with the Severity
                    attribute set to either:
                     o HardError,
                     o Warning but the Consumer decides to not
                       continue with the transaction
                     o TransientError and the transaction has
                       subsequently timed out.
                    See section 7.21.1 Error Processing Guidelines for
                    more details.
                    This attribute:
                     o must not be present when TradingRole is set to
                       Consumer or DelivTo,
                     o must be present when TradingRole is set to
                       Merchant, PaymentHandler or DeliveryHandler.
                    The content of this attribute is dependent on the
                    Transport Mechanism see the Transport Mechanism
                    Supplement.
 ErrorLogNetLocn    Optional. This contains the net location that
                    Consumers should send IOTP Messages that contain
                    Error Blocks with an Error Component with the
                    Severity attribute set to either:
                     o HardError,
                     o Warning but the Consumer decides to not
                       continue with the transaction
                     o TransientError and the transaction has
                       subsequently timed out.
                    This attribute:
                     o must not be present when TradingRole is set to
                       Consumer role,

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                     o must be present when TradingRole is set to
                       Merchant, PaymentHandler or DeliveryHandler.
                    The content of this attribute is dependent on the
                    Transport Mechanism see the Transport Mechanism
                    Supplement.
                    The ErrorLogNetLocn can be used to send error
                    messages to the software company or some other
                    Organisation responsible for fixing problems in
                    the software which sent the incoming message. See
                    section 7.21.1 Error Processing Guidelines for
                    more details.

7.6.3 Contact Information Element

 This contains information which can be used to contact an
 Organisation or an individual. All attributes are optional however at
 least one item of contact information should be present. Its
 definition is as follows.
 <!ELEMENT ContactInfo EMPTY >
 <!ATTLIST ContactInfo
  xml:lang           NMTOKEN #IMPLIED
  Tel                CDATA   #IMPLIED
  Fax                CDATA   #IMPLIED
  Email              CDATA   #IMPLIED
  NetLocn            CDATA   #IMPLIED >
 Attributes:
 xml:lang           Defines the language used by attributes within
                    this element. See section 3.8 Identifying
                    Languages.
 Tel                A telephone number by which the Organisation may
                    be contacted. Note that this is a text field and
                    no validation is carried out on it.
 Fax                A fax number by which the Organisation may be
                    contacted. Note that this is a text field and no
                    validation is carried out on it.
 Email              An email address by which the Organisation may be
                    contacted. Note that this field should conform to
                    the conventions for address specifications
                    contained in [RFC822].

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 NetLocn            A location on the Internet by which information
                    about the Organisation may be obtained that can be
                    displayed using a web browser.
                    The content of this attribute must conform to
                    [RFC1738].

7.6.4 Person Name Element

 This contains the name of an individual person. All fields are
 optional however as a minimum either the GivenName or the FamilyName
 should be present. Its definition is as follows.
 <!ELEMENT PersonName EMPTY >
 <!ATTLIST PersonName
  xml:lang           NMTOKEN #IMPLIED
  Title              CDATA   #IMPLIED
  GivenName          CDATA   #IMPLIED
  Initials           CDATA   #IMPLIED
  FamilyName         CDATA   #IMPLIED >
 Attributes:
 xml:lang           Defines the language used by attributes within
                    this element. See section 3.8 Identifying
                    Languages.
 Title              A distinctive name; personal appellation,
                    hereditary or not, denoting or implying office
                    (e.g., judge, mayor) or nobility (e.g., duke,
                    duchess, earl), or used in addressing or referring
                    to a person (e.g., Mr, Mrs, Miss)
 GivenName          The primary or main name by which a person is
                    known amongst and identified by their family,
                    friends and acquaintances. Otherwise known as
                    first name or Christian Name.
 Initials           The first letter of the secondary names (other
                    than the Given Name) by which a person is known
                    amongst or identified by their family, friends and
                    acquaintances.
 FamilyName         The name by which family of related individuals
                    are known. It is typically the part of an
                    individual's name which is passed on by parents to
                    their children.

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7.6.5 Postal Address Element

 This contains an address which can be used, for example, for the
 physical delivery of goods, services or letters. Its definition is as
 follows.
 <!ELEMENT PostalAddress EMPTY >
 <!ATTLIST PostalAddress
  xml:lang           NMTOKEN #IMPLIED
  AddressLine1       CDATA   #IMPLIED
  AddressLine2       CDATA   #IMPLIED
  CityOrTown         CDATA   #IMPLIED
  StateOrRegion      CDATA   #IMPLIED
  PostalCode         CDATA   #IMPLIED
  Country            CDATA   #IMPLIED
  LegalLocation (True | False) 'False' >
 Attributes:
 xml:lang           Defines the language used by attributes within
                    this element. See section 3.8 Identifying
                    Languages.
 AddressLine1       The first line of a postal address. e.g., "The
                    Meadows"
 AddressLine2       The second line of a postal address. e.g., "Sandy
                    Lane"
 CityOrTown         The city of town of the address. e.g., "Carpham"
 StateOrRegion      The state or region within a country where the
                    city or town is placed. e.g., "Surrey"
 PostalCode        The code known as, for example a post code or zip
                    code, that is typically used by Postal
                    Organisations to organise postal deliveries into
                    efficient sequences. e.g., "KT22 1AA"
 Country            The country for the address. e.g., "UK"
 LegalLocation      This identifies whether the address is the
                    Registered Address for the Organisation. At least
                    one address for the Organisation must have a value
                    set to True unless the Trading Role is either
                    Consumer or DeliverTo.

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7.7 Brand List Component

 Brand List Components are contained within the Trading Protocol
 Options Block (see section 8.1) of the IOTP Transaction. They
 contains lists of:
 o  payment Brands (see also section 11.1 Brand Definitions and Brand
    Selection),
 o  amounts to be paid in the currencies that are accepted or offered
    by the Merchant,
 o  the payment protocols which can be used to make payments with a
    Brand, and
 o  the net locations of the Payment Handlers which accept payment for
    a payment protocol
 The definition of a Brand List Component is as follows.
 <!ELEMENT BrandList (Brand+, ProtocolAmount+,
  CurrencyAmount+, PayProtocol+) >
 <!ATTLIST BrandList
  ID                 ID      #REQUIRED
  xml:lang           NMTOKEN #REQUIRED
  ShortDesc          CDATA   #REQUIRED
  PayDirection (Debit | Credit) #REQUIRED >
 Attributes:
 ID                 An identifier which uniquely identifies the Brand
                    List Component within the IOTP Transaction.
 xml:lang           Defines the language used by attributes or child
                    elements within this component, unless overridden
                    by an xml:lang attribute on a child element. See
                    section 3.8 Identifying Languages.
 ShortDesc          A text description in the language defined by
                    xml:Lang giving details of the purpose of the
                    Brand List.  This information must be displayed to
                    the receiver of the Brand List in order to assist
                    with making the selection. It is of particular
                    benefit in allowing a Consumer to distinguish the
                    purpose of a Brand List when an IOTP Transaction
                    involves more than one payment.

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 PayDirection       Indicates the direction in which the payment for
                    which a Brand is being selected is to be made. Its
                    values may be:
                     o Debit The sender of the Payment Request Block
                       (e.g., the Consumer) to which this Brand List
                       relates will make the payment to the Payment
                       Handler, or
                     o Credit The sender of the Payment Request Block
                       to which this Brand List relates will receive a
                       payment from the Payment Handler.
 Content:
 Brand              This describes a Brand. The sequence of the Brand
                    elements (see section 7.7.1) within the Brand List
                    does not indicate any preference. It is
                    recommended that software which processes this
                    Brand List presents Brands in a sequence which the
                    receiver of the Brand List prefers.
 ProtocolAmount     This links a particular Brand to:
                     o the currencies and amounts in CurrencyAmount
                       elements that can be used with the Brand, and
                     o the Payment Protocols and Payment Handlers,
                       which can be used with those currencies and
                       amounts, and a particular Brand
 CurrencyAmount     This contains a currency code and an amount.
 PayProtocol        This contains information about a Payment Protocol
                    and the Payment Handler which may be used with a
                    particular Brand.
 The relationships between the elements which make up the content of
 the Brand List is illustrated in the diagram below.

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  • +*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*
                  Brand List Component
                    |                   ProtocolAmountRefs
                    |-Brand Element-----------------------------
                    |  |                                        |
                    |   - Protocol Brand Element--------        |
                    |                                   |       |
                    |                         ProtocolId|       |
                    |                                   |       |
                    |-Protocol Amount Element<----------+-------
                    |  |                      |         |
                    |  |                      |         |
                    |  |CurrencyAmountRefs    |Pay      |
                    |  |                      |Protocol |
                    |  v                      |Ref      |
                    |-Currency Amount Element |         |
                    | Element                 |         |
                    |                         |         |
                     -PayProtocolElement<------<--------
  • -*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*
                 Figure 15 Brand List Element Relationships
 Examples of complete Brand Lists are contained in section 11.2 Brand
 List Examples.

7.7.1 Brand Element

 A Brand Element describes a brand that can be used for making a
 payment.  One or more of these elements is carried in each Brand List
 Component that has the PayDirection attribute set to Debit.  Exactly
 one Brand Element may be carried in a Brand List Component that has
 the PayDirection attribute set to Credit.
 <!ELEMENT Brand (ProtocolBrand*, PackagedContent*) >
 <!ATTLIST Brand
  ID                 ID      #REQUIRED
  xml:lang           NMTOKEN #IMPLIED
  BrandId            CDATA   #REQUIRED
  BrandName          CDATA   #REQUIRED
  BrandLogoNetLocn   CDATA   #REQUIRED
  BrandNarrative     CDATA   #IMPLIED
  ProtocolAmountRefs IDREFS  #REQUIRED
  ContentSoftwareId  CDATA   #IMPLIED >

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 Attributes:
 ID                  Element identifier, potentially referenced in a
                     Brand Selection Component contained in a later
                     Payment Request message and uniquely identifies
                     the Brand element within the IOTP Transaction.
 xml:lang            Defines the language used by attributes and
                     content of this element. See section 3.8
                     Identifying Languages.
 BrandId             This contains a unique identifier for the brand
                     (or promotional brand). It is used to match
                     against a list of Payment Instruments which the
                     Consumer holds to determine whether or not the
                     Consumer can pay using the Brand.
                     Values of BrandId are managed under the procedure
                     described in section 12 IANA Considerations.
                     As values of BrandId are controlled under the
                     procedures defined in section 12 IANA
                     Considerations user defined values may be
                     defined.
 BrandName           This contains the name of the brand, for example
                     MasterCard Credit. This is the description of the
                     Brand which is displayed to the consumer in the
                     Consumers language defined by xml:lang. For
                     example it might be "American Airlines Advantage
                     Visa". Note that this attribute is not used for
                     matching against the payment instruments held by
                     the Consumer.
 BrandLogoNetLocn    The net location which can be used to download
                     the logo for the Organisation. See section
                     Retrieving Logos (see section 10).
                     The content of this attribute must conform to
                     [RFC1738].
 BrandNarrative      This optional attribute is designed to be used by
                     the Merchant to indicate some special conditions
                     or benefit which would apply if the Consumer
                     selected that brand. For example "5% discount",
                     "free shipping and handling", "free breakage
                     insurance for 1 year", "double air miles apply",
                     etc.

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 ProtocolAmountRefs  Identifies the protocols and related currencies
                     and amounts which can be used with this Brand.
                     Specified as a list of ID's of Protocol Amount
                     Elements (see section 7.7.3) contained within the
                     Brand List.
 ContentSoftwareId   See section 14.Glossary.
 Content:
 ProtocolBrand      Protocol Brand elements contain brand information
                    to be used with a specific payment protocol (see
                    section 7.7.2)
 PackagedContent    Optional Packaged Content (see section 3.7)
                    elements containing information about the brand
                    which may be used by the payment protocol. The
                    content of this information is defined in the
                    supplement for a payment protocol which describes
                    how the payment protocol works with IOTP.
 Example Brand Elements are contained in section 11.2 Brand List
 Examples.

7.7.2 Protocol Brand Element

 The Protocol Brand Element contains information that is specific to
 the use of a particular Protocol with a Brand. Its definition is as
 follows.
 <!ELEMENT ProtocolBrand (PackagedContent*) >
 <!ATTLIST ProtocolBrand
  ProtocolId         CDATA   #REQUIRED
  ProtocolBrandId    CDATA   #REQUIRED >
 Attributes:
 ProtocolId         This must match the value of a ProtocolId
                    attribute in a Pay Protocol Element (see section
                    7.7.5).
                    The values of ProtocolId should be unique within a
                    Brand Element otherwise there is an error.

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 ProtocolBrandId    This is the Payment Brand Id to be used with a
                    particular payment protocol. For example, SET and
                    EMV have their own well defined, yet different,
                    values for the Brand Id to be used with each
                    protocol.
                    The valid values of this attribute are defined in
                    the supplement for the payment protocol identified
                    by ProtocolId that describes how the payment
                    protocol works with IOTP.
 Content:
 PackagedContent    Optional Packaged Content (see section 3.7)
                    elements containing information about the
                    protocol/brand which may be used by the payment
                    protocol. The content of this information is
                    defined in the supplement for a payment protocol
                    which describes how the payment protocol works
                    with IOTP.

7.7.3 Protocol Amount Element

 The Protocol Amount element links a Brand to:
 o  the currencies and amounts in Currency Amount Elements (see
    section 7.7.4) that can be used with the Brand, and
 o  the Payment Protocols and Payment Handlers defined in a Pay
    Protocol Element (see section 7.7.5), which can be used with those
    currencies and amounts.
 Its definition is as follows:
 <!ELEMENT ProtocolAmount (PackagedContent*) >
 <!ATTLIST ProtocolAmount
  ID                 ID      #REQUIRED
  PayProtocolRef     IDREF   #REQUIRED
  CurrencyAmountRefs IDREFS  #REQUIRED
  ContentSoftwareId  CDATA   #IMPLIED >
 Attributes:
 ID                  Element identifier, potentially referenced in a
                     Brand element; or in a Brand Selection Component
                     contained in a later Payment Request message
                     which uniquely identifies the Protocol Amount
                     element within the IOTP Transaction.

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 PayProtocolRef      Contains an Element Reference (see section 3.5)
                     that refers to the Pay Protocol Element (see
                     section 7.7.5) that contains the Payment Protocol
                     and Payment Handlers that can be used with the
                     Brand.
 CurrencyAmountRefs  Contains a list of  Element References (see
                     section 3.5) that refer to the Currency Amount
                     Element (see section 7.7.4) that describes the
                     currencies and amounts that can be used with the
                     Brand.
 ContentSoftwareId   See section 14. Glossary.
 Content:
 PackagedContent    Optional Packaged Content (see section 3.7)
                    elements containing information about the protocol
                    amount which may be used by the payment protocol.
                    The content of this information is defined in the
                    supplement for a payment protocol which describes
                    how the payment protocol works with IOTP.
 Examples of Protocol Amount Elements are contained in section 11.2
 Brand List Examples.

7.7.4 Currency Amount Element

 A Currency Amount element contains:
 o a currency code (and its type), and
 o an amount.
 One or more of these elements is carried in each Brand List
 Component.  Its definition is as follows:
 <!ELEMENT CurrencyAmount EMPTY >
 <!ATTLIST CurrencyAmount
  ID                 ID      #REQUIRED
  Amount             CDATA   #REQUIRED
  CurrCodeType       NMTOKEN 'ISO4217-A'
  CurrCode           CDATA   #REQUIRED >
 Attributes:
 ID                 Element identifier, potentially referenced in a
                    Brand element; or in a Brand Selection Component

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                    contained in a later Payment Request message which
                    uniquely identifies the Currency Amount Element
                    within the IOTP Transaction.
 Amount             Indicates the amount to be paid in whole and
                    fractional units of the currency. For example
                    $245.35 would be expressed "245.35". Note that
                    values smaller than the smallest denomination are
                    allowed. For example one tenth of a cent would be
                    "0.001".
 CurrCodeType       Indicates the domain of the CurrCode. This
                    attribute is included so that the currency code
                    may support non-standard "currencies" such as
                    frequent flyer points, trading stamps, etc. Its
                    values may be:
                     o ISO4217-A (the default) indicates the currency
                       code is a three character alphabetic currency
                       code that conforms to [ISO 4217]
                     o IOTP indicates that values of CurrCode are
                       managed under the procedure described in
                       section 12 IANA Considerations
 CurrCode           A code which identifies the currency to be used in
                    the payment. The domain of valid currency codes is
                    defined by CurrCodeType
                    As values of CurrCodeType are managed under the
                    procedure described in section 12 IANA
                    Considerations user defined values of CurrCodeType
                    may be defined.
 Examples of Currency Amount Elements are contained in section 11.2
 Brand List Examples.

7.7.5 Pay Protocol Element

 A Pay Protocol element specifies details of a Payment Protocol and
 the Payment Handler that can be used with a Brand. One or more of
 these elements is carried in each Brand List.
 <!ELEMENT PayProtocol (PackagedContent*) >
 <!ATTLIST PayProtocol
  ID                 ID      #REQUIRED
  xml:lang           NMTOKEN #IMPLIED
  ProtocolId         NMTOKEN #REQUIRED
  ProtocolName       CDATA   #REQUIRED
  ActionOrgRef       NMTOKEN #REQUIRED

Burdett Informational [Page 118] RFC 2801 IOTP/1.0 April 2000

  PayReqNetLocn      CDATA   #IMPLIED
  SecPayReqNetLocn   CDATA   #IMPLIED
  ContentSoftwareId  CDATA   #IMPLIED >
 Attributes:
 ID                 Element identifier, potentially referenced in a
                    Brand element; or in a Brand Selection Component
                    contained in a later Payment Request message which
                    uniquely identifies the Pay Protocol element
                    within the IOTP Transaction.
 xml:lang           Defines the language used by attributes and
                    content of this element. See section 3.8
                    Identifying Languages.
 ProtocolId         Consists of a protocol name and version. For
                    example "SETv1.0".
                    The values of ProtocolId are defined by the
                    payment scheme/method owners in the document that
                    describes how to encapsulate a payment protocol
                    within IOTP.
 ProtocolName       A narrative description of the payment protocol
                    and its version in the language identified by
                    xml:lang. For example "Secure Electronic
                    Transaction Version 1.0". Its purpose is to help
                    provide information on the payment protocol being
                    used if problems arise.
 ActionOrgRef       An Element Reference (see section 3.5) to the
                    Organisation Component for the Payment Handler for
                    the Payment Protocol.
 PayReqNetLocn      The Net Location indicating where an unsecured
                    Payment Request message should be sent if this
                    protocol choice is used.
                    The content of this attribute is dependent on the
                    Transport Mechanism (such must conform to
                    [RFC1738].
 SecPayReqNetLocn   The Net Location indicating where a secured
                    Payment Request message should be sent if this
                    protocol choice is used.

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                    A secured payment involves the use of a secure
                    channel such as [SSL/TLS] in order to communicate
                    with the Payment Handler.
                    The content of this attribute must conform to
                    [RFC1738]. See also See section 3.9 Secure and
                    Insecure Net Locations.
 ContentSoftwareId  See section 14. Glossary.
 Content:
 PackagedContent    Optional Packaged Content elements (see section
                    3.7) containing information about the protocol
                    which is used by the payment protocol. The content
                    of this information is defined in the supplement
                    for a payment protocol which describes how the
                    payment protocol works with IOTP. An example of
                    its use could be to include a payment protocol
                    message.
 Examples of Pay Protocol Elements are contained in section 11.2 Brand
 List Examples.

7.8 Brand Selection Component

 A Brand Selection Component identifies the choice of payment brand,
 payment protocol and the Payment Handler.  This element is used:
 o  in Payment Request messages within Baseline Purchase and Baseline
    Value Exchange IOTP Transactions to identify the brand, protocol
    and payment handler for a payment, or
 o  to, optionally, inform a merchant in a purchase of the payment
    brand being used so that the offer and order details can be
    amended accordingly.
 In Baseline IOTP, the integrity of Brand Selection Components is not
 guaranteed.  However, modification of Brand Selection Components can
 only cause denial of service if the payment protocol itself is secure
 against message modification, duplication, and swapping attacks.
 The definition of a Brand Selection Component is as follows.
 <!ELEMENT BrandSelection (BrandSelBrandInfo?,
      BrandSelProtocolAmountInfo?,
      BrandSelCurrencyAmountInfo?) >
 <!ATTLIST BrandSelection

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  ID                 ID      #REQUIRED
  BrandListRef       NMTOKEN #REQUIRED
  BrandRef           NMTOKEN #REQUIRED
  ProtocolAmountRef  NMTOKEN #REQUIRED
  CurrencyAmountRef  NMTOKEN #REQUIRED >
 Attributes:
 ID                 An identifier which uniquely identifies the Brand
                    Selection Component within the IOTP Transaction.
 BrandListRef       The Element Reference (see section 3.5) of the
                    Brand List Component from which a Brand is being
                    selected
 BrandRef           The Element Reference of a Brand element within
                    the Brand List Component that is being selected
                    that is to be used in the payment.
 ProtocolAmountRef  The Element Reference of a Protocol Amount element
                    within the Brand List Component which is to be
                    used when making the payment.
 CurrencyAmountRef  The Element Reference of a Currency Amount element
                    within the Brand List Component which is to be
                    used when making the payment.
 Content:
 BrandSelBrandInfo,           This contains any additional data that
 BrandSelProtocolAmountInfo,  may be required by a particular payment
 BrandSelCurrencyAmountInfo   brand or protocol. See sections 7.8.1,
                               7.8.2, and 7.8.3.
 The following rules apply:
 o  the BrandListRef must contain the ID of a Brand List Component in
    the same IOTP Transaction
 o  every Brand List Component in the Trading Protocol Options Block
    (see section 8.1) must be referenced by one and only one Brand
    Selection Component
 o  the BrandRef must refer to the ID of a Brand contained within the
    Brand List Component referred to by BrandListRef

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 o  the ProtocolAmountRef must refer to one of the Element IDs listed
    in the ProtocolAmountRefs attribute of the Brand element
    identified by BrandRef
 o  the CurrencyAmountRef must refer to one of the Element IDs listed
    in the CurrencyAmountRefs attribute of the Protocol Amount Element
    identified by ProtocolAmountRef.
 An example of a Brand Selection Component is included in 11.2 Brand
 List Examples.

7.8.1 Brand Selection Brand Info Element

 The Brand Selection Brand Info Element contains any additional data
 that may be required by a particular payment brand. See the IOTP
 payment method supplement for a description of how and when it used.
 <!ELEMENT BrandSelBrandInfo (PackagedContent+) >
 <!ATTLIST BrandSelBrandInfo
  ID                 ID      #REQUIRED
  ContentSoftwareId  CDATA   #IMPLIED >
 Attributes:
 ContentSoftwareId  See section 14. Glossary.
 Content:
 PackagedContent    Packaged Content elements (see section 3.7) that
                    contain additional data that may be required by a
                    particular payment brand. See the payment method
                    supplement for IOTP for rules on how this is used.

7.8.2 Brand Selection Protocol Amount Info Element

 The Brand Selection Protocol Amount Info Element contains any
 additional data that is payment protocol specific that may be
 required by a particular payment brand or payment protocol. See the
 IOTP payment method supplement for a description of how and when it
 used.
 <!ELEMENT BrandSelProtocolAmountInfo (PackagedContent+) >
 <!ATTLIST BrandSelProtocolAmountInfo
  ID                 ID      #REQUIRED
  ContentSoftwareId  CDATA   #IMPLIED >

Burdett Informational [Page 122] RFC 2801 IOTP/1.0 April 2000

 Attributes:
 ContentSoftwareId  See section 14. Glossary.
 Content:
 PackagedContent    Packaged Content elements (see section 3.7) that
                    may contain additional data that may be required
                    by a particular payment brand. See the payment
                    method supplement for IOTP for rules on how this
                    is used.

7.8.3 Brand Selection Currency Amount Info Element

 The Brand Selection Currency Amount Info Element contains any
 additional data that is payment brand and currency specific that may
 be required by a particular payment brand. See the IOTP payment
 method supplement for a description of how and when it used.
 <!ELEMENT BrandSelCurrencyAmountInfo (PackagedContent+) >
 <!ATTLIST BrandSelCurrencyAmountInfo
  ID                 ID      #REQUIRED
  ContentSoftwareId  CDATA   #IMPLIED >
 Attributes:
 ContentSoftwareId  See section 14. Glossary.
 Content:
 PackagedContent    Packaged Content elements (see section 3.7) that
                    contain additional data relating to the payment
                    brand and currency. See the payment method
                    supplement for IOTP for rules on how this is used.

7.9 Payment Component

 A Payment Component contains information used to control how a
 payment is carried out. Its provides information on:
 o  the times within which a Payment with a Payment Handler may be
    started
 o  a reference to the Brand List (see section 7.7) which identifies
    the Brands, protocols, currencies and amounts which can be used to
    make a payment
 o  whether or not a payment receipt will be provided

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 o  whether another payment precedes this payment.
 Its definition is as follows.
 <!ELEMENT Payment EMPTY >
 <!ATTLIST Payment
  ID                 ID      #REQUIRED
  OkFrom             CDATA   #REQUIRED
  OkTo               CDATA   #REQUIRED
  BrandListRef       NMTOKEN #REQUIRED
  SignedPayReceipt (True | False) #REQUIRED
  StartAfterRefs     NMTOKENS #IMPLIED >
 Attributes:
 ID                 An identifier which uniquely identifies the
                    Payment Component within the IOTP Transaction.
 OkFrom             The date and time in [UTC] format after which a
                    Payment Handler may accept for processing a
                    Payment Request Block (see section 8.7) containing
                    the Payment Component.
 OkTo               The date and time in [UTC] format before which a
                    Payment Handler may accept for processing a
                    Payment Request Block containing the Payment
                    Component.
 BrandListRef       An Element Reference (see section 3.5) of a Brand
                    List Component (see section 7.7) within the TPO
                    Trading Block for the IOTP Transaction. The Brand
                    List identifies the alternative ways in which the
                    payment can be made.
 SignedPayReceipt   Indicates whether or not the Payment Response
                    Block (see section 8.9) generated by the Payment
                    Handler for the payment must be digitally signed.
 StartAfter         Contains Element References (see section 3.5) of
                    other Payment Components which describe payments
                    which must be complete before this payment can
                    start. If no StartAfter attribute is present then
                    there are no dependencies and the payment can
                    start immediately

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7.10 Payment Scheme Component

 A Payment Scheme Component contains payment protocol information for
 a specific payment scheme which is transferred between the parties
 involved in a payment for example a [SET] message. Its definition is
 as follows.
 <!ELEMENT PaySchemeData (PackagedContent+) >
 <!ATTLIST PaySchemeData
  ID                 ID      #REQUIRED
  PaymentRef         NMTOKEN #IMPLIED
  ConsumerPaymentId  CDATA   #IMPLIED
  PaymentHandlerPayId CDATA  #IMPLIED
  ContentSoftwareId  CDATA   #IMPLIED >
 Attributes:
 ID                   An identifier which uniquely identifies the
                      Payment Scheme Component within the IOTP
                      Transaction.
 PaymentRef           An Element Reference (see section 3.5) to the
                      Payment Component (see section 7.9) to which
                      this Payment Scheme Component relates. It is
                      required unless the Payment Scheme Component is
                      part of an Transaction Inquiry Status
                      Transaction (see section 9.2.1).
 ConsumerPaymentId    An identifier specified by the Consumer which,
                      if returned by the Payment Handler in another
                      Payment Scheme Component or by other means, will
                      enable the Consumer to identify which payment is
                      being referred to.
 PaymentHandlerPayId  An identifier specified by the Payment Handler
                      which, if returned by the Consumer in another
                      Payment Scheme Component, or by other means,
                      will enable the Payment Handler to identify
                      which payment is being referred to. It is
                      required on every Payment Scheme Component apart
                      from the one contained in a Payment Request
                      Block.
 ContentSoftwareId    See section 14. Glossary.

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 Content:
 PackagedContent    Contains payment scheme protocol information as
                    Packaged Content elements (see section 3.7). See
                    the payment scheme supplement for the definition
                    of its content.
                    Note that:
                     o the values of the Name attribute of each
                       packaged content element are defined by the
                       Payment Protocol Supplement
                     o the value of each Name must be unique within a
                       Payment where a Payment is defined as all
                       Payment Scheme or Payment Receipt Components
                       with the same value of the PaymentRef attribute

7.11 Payment Receipt Component

 A Payment Receipt is a record of a payment which demonstrates how
 much money has been paid or received. It is distinct from a purchase
 receipt in that it contains no record of what was being purchased.
 Typically the content of a Payment Receipt Component will contain
 data which describes:
 o  the amount paid and its currency
 o  the date and time of the payment
 o  internal reference numbers which identify the payment to the
    payment system
 o  potentially digital signatures generated by the payment method
    which can be used to prove after the event that the payment
    occurred.
 If the Payment Method being used provides the facility then the
 Payment Receipt Component should contain payment protocol messages,
 or references to messages, which prove the payment occurred.
 The precise definition of the content is Payment Method dependent.
 Refer to the supplement for the payment method being used to
 determine the rules that apply.
 Information contained in the Payment Receipt Component should be
 displayed or otherwise made available to the Consumer.

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 Note: If the Payment Receipt Component contains Payment Protocol
 Messages, then the Messages will need to be processed by Payment
 Method software to convert it into a format which can be understood
 by the Consumer
  The definition of a Payment Receipt Component is as follows.
 <!ELEMENT PayReceipt (PackagedContent*) >
 <!ATTLIST PayReceipt
  ID                 ID      #REQUIRED
  PaymentRef         NMTOKEN #REQUIRED
  PayReceiptNameRefs NMTOKENS #IMPLIED
  ContentSoftwareId  CDATA   #IMPLIED >
 Attributes:
 ID                  An identifier which uniquely identifies the
                     Payment Receipt Component within the IOTP
                     Transaction.
 PaymentRef          Contains an Element Reference (see section 3.5)
                     to the Payment Component (see section 7.9) to
                     which this payment receipt applies
 PayReceiptNameRefs  Optionally contains a list of the values of the
                     Name attributes of Packaged Content elements that
                     together make up the receipt. The Packaged
                     Content elements are contained either within:
                      o Payment Scheme Data components exchanged
                        between the Payment Handler and the Consumer
                        roles during the Payment, and/or
                      o the Payment Receipt component itself.
                     Note that:
                      o each payment scheme defines in its supplement
                        the Names of the Packaged Content elements
                        that must be listed in this attribute (if
                        any).
                      o if a Payment Scheme Component contains
                        Packaged Content elements with a name that
                        matches a name within PayReceiptNameRefs, then
                        those Payment Scheme Components must be
                        referenced by Digests in the Payment Response
                        signature component (if such a signature is
                        being used)
                     The client software should save all the
                     components referenced so that the payment receipt
                     can be reconstructed when required.

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 ContentSoftwareId   See section 14. Glossary.
 Content:
 PackagedContent    Optionally contains payment scheme payment receipt
                    information as Packaged Content elements (see
                    section 3.7). See the payment scheme supplement
                    for the definition of its content.
                    Note that:
                     o the values of the Name attribute of each
                       packaged content element are defined by the
                       Payment Protocol Supplement
                     o the value of each Name must be unique within a
                       Payment where a Payment is defined as all
                       Payment Scheme or Payment Receipt Components,
                       with the same value of the PaymentRef attribute
 Note that either the PayReceiptNameRefs attribute, the
 PackagedContent element, or both must be present.

7.12 Payment Note Component

 The Payment Note Component contains additional, non payment related,
 information which the Payment Handler wants to provide to the
 Consumer.  For example, if a withdrawal or deposit were being made
 then it could contain information on the remaining balance on the
 account after the transfer was complete. The information should
 duplicate information contained within the Payment Receipt Component.
 Information contained in the Payment Note Component should be
 displayed or otherwise made available to the Consumer. For
 interoperability, the Payment Note Component should support, as a
 minimum, the content types of "Plain Text", HTML and XML. Its
 definition is as follows.
 <!ELEMENT PaymentNote (PackagedContent+) >
 <!ATTLIST PaymentNote
   ID                ID      #REQUIRED
   ContentSoftwareId CDATA   #IMPLIED >
 Attributes:
 ID                 An identifier which uniquely identifies the
                    Payment Receipt Component within the IOTP
                    Transaction.
 ContentSoftwareId  See section 14. Glossary.

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 Content:
 PackagedContent    Contains additional, non payment related,
                    information which the Payment Handler wants to
                    provide to the Consumer as one or more Packaged
                    Content elements (see section 3.7).

7.13 Delivery Component

 The Delivery Element contains information required to deliver goods
 or services. Its definition is as follows.
 <!ELEMENT Delivery (DeliveryData?, PackagedContent*) >
 <!ATTLIST Delivery
  ID                 ID      #REQUIRED
  xml:lang           NMTOKEN #REQUIRED
  DelivExch          (True | False) #REQUIRED
  DelivAndPayResp    (True | False) #REQUIRED
  ActionOrgRef       NMTOKEN #IMPLIED >
 Attributes:
 ID                  An identifier which uniquely identifies the
                     Delivery Component within the IOTP Transaction.
 xml:lang            Defines the language used by attributes or child
                     elements within this component, unless overridden
                     by an xml:lang attribute on a child element. See
                     section 3.8 Identifying Languages.
 DelivExch           Indicates if this IOTP Transaction includes the
                     messages associated with a Delivery Exchange.
                     Valid values are:
                      o True indicates it does include a Delivery
                        Exchange
                      o False indicates it does not include a
                        Delivery Exchange
                     If set to true then a DeliveryData element must
                     be present. If set to false it may be absent.
 DelivAndPayResp     Indicates if the Delivery Response Block (see
                     section 8.11) and the Payment Response Block (see
                     section 8.9 ) are combined into one IOTP Message.
                     Valid values are:
                      o True indicates both blocks will be in the
                        same IOTP Message, and

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                      o False indicates each block will be in a
                        different IOTP Message
                     DelivAndPayResp should not be true if DelivExch
                     is False.
                     In practice combining the Delivery Response Block
                     and Payment Response Block is only likely to be
                     practical if the Merchant, the Payment Handler
                     and the Delivery Handler are the same
                     Organisation since:
                      o the Payment Handler must have access to Order
                        Component information so that they know what
                        to deliver, and
                      o the Payment Handler must be able to carry out
                        the delivery
 ActionOrgRef        An Element Reference to the Organisation
                     Component of the Delivery Handler for this
                     delivery.
 Content:
 DeliveryData       Contains details about how the delivery will be
                    carried out. See 7.13.1 Delivery Data Element
                    below.
 PackagedContent    Contains "user" data defined for the Merchant
                    which is required by the Delivery Handler as one
                    or more Packaged Content Elements see section 3.7.

7.13.1 Delivery Data Element

 The DeliveryData element contains information about where and how
 goods are to be delivered. Its definition is as follows.
 <!ELEMENT DeliveryData (PackagedContent*) >
 <!ATTLIST DeliveryData
  xml:lang           NMTOKEN #IMPLIED
  OkFrom             CDATA   #REQUIRED
  OkTo               CDATA   #REQUIRED
  DelivMethod        NMTOKEN #REQUIRED
  DelivToRef         NMTOKEN #REQUIRED
  DelivReqNetLocn    CDATA   #REQUIRED
  SecDelivReqNetLocn CDATA   #REQUIRED
  ContentSoftwareId  CDATA   #IMPLIED >

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 Attributes:
 xml:lang            Defines the language used by attributes within
                     this component. See section 3.8 Identifying
                     Languages.
 OkFrom              The date and time in [UTC] format after which the
                     Delivery Handler may accept for processing a
                     Delivery Request Block (see section 8.10).
 OkTo                The date and time in [UTC] format before which
                     the Delivery Handler may accept for processing a
                     Delivery Request Block.
 DelivMethod         Indicates the method by which goods or services
                     may be delivered. Valid values are:
                      o Post the goods will be delivered by post or
                        courier
                      o Web the goods will be delivered
                        electronically in the Delivery Note Component
                      o Email the goods will be delivered
                        electronically by e-mail
                     Values of DelivMethod are managed under the
                     procedure described in section 12 IANA
                     Considerations which allows user defined codes to
                     be defined.
 DelivToRef          The Element Reference (see section 3.4) of an
                     Organisation Component within the IOTP
                     Transaction which has a role of DelivTo. The
                     information in this block is used to determine
                     where delivery is to be made. It must be
                     compatible with DelivMethod. Specifically if the
                     DelivMethod is:
                      o Post, then the there must be a Postal Address
                        Element containing sufficient information for
                        a postal delivery,
                      o Web, then there are no specific requirements.
                        The information will be sent in a web page
                        back to the Consumer
                      o Email, then there must be Contact Information
                        Element with a valid e-mail address
 DelivReqNetLocn     This contains the Net Location to which an
                     unsecured Delivery Request Block (see section
                     8.10) which contains the Delivery Component
                     should be sent.

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                     The content of this attribute is dependent on the
                     Transport Mechanism and must conform to
                     [RFC1738].
 SecDelivReqNetLocn  This contains the Net Location to which a secured
                     Delivery Request Block (see section 8.10) which
                     contains the Delivery Component should be sent.
                     A secured delivery request involves the use of a
                     secure channel such as [SSL/TLS] in order to
                     communicate with the Payment Handler.
                     The content of this attribute is dependent on the
                     Transport Mechanism must conform to [RFC1738].
                     See also Section 3.9 Secure and Insecure Net
                     Locations.
 ContentSoftwareId   See section 14. Glossary.
 Content:
 PackagedContent    Additional information about the delivery as one
                    or more Packaged Content elements (see section
                    3.7) provided to the Delivery Handler by the
                    merchant.

7.14 Consumer Delivery Data Component

 A Consumer Delivery Data Component is used by a Consumer to specify
 an identifier that can be used by the Consumer to identify the
 Delivery.
 Its definition is as follows:
 <!ELEMENT ConsumerDeliveryData EMPTY >
 <!ATTLIST ConsumerDeliveryData
  ID                 ID      #REQUIRED
  ConsumerDeliveryId CDATA   #REQUIRED>
 Attributes:
 ID                  An identifier which uniquely identifies the
                     Consumer Delivery Data Component within the IOTP
                     Transaction.

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 ConsumerDeliveryId  An identifier specified by the Consumer which, if
                     returned by the Delivery Handler will enable the
                     Consumer to identify which Delivery is being
                     referred to.

7.15 Delivery Note Component

 A Delivery Note contains delivery instructions about the delivery of
 goods or services or potentially the actual Delivery Information
 itself.  It is information which the person or Organisation receiving
 the Delivery Note can use when delivery occurs.
 For interoperability, the Delivery Note Component Packaged Content
 should support both Plain Text, HTML and XML.
 It's definition is as follows.
 <!ELEMENT DeliveryNote (PackagedContent+) >
 <!ATTLIST DeliveryNote
  ID                 ID      #REQUIRED
  xml:lang           NMTOKEN #REQUIRED
  DelivHandlerDelivId CDATA  #IMPLIED
  ContentSoftwareId  CDATA   #IMPLIED >
 Attributes:
 ID                   An identifier which uniquely identifies the
                      Delivery Note Component within the IOTP
                      Transaction.
 xml:lang             Defines the language used by attributes or child
                      elements within this component, unless
                      overridden by an xml:lang attribute on a child
                      element. See section 3.8 Identifying Languages.
 DelivHandlerDelivId  An optional identifier specified by the Delivery
                      Handler which, if returned by the Consumer in
                      another Delivery Component, or by other means,
                      will enable the Delivery Handler to identify
                      which Delivery is being referred to. It is
                      required on every Delivery Component apart from
                      the one contained in a Delivery Request Block.
                      An example use of this attribute is to contain a
                      delivery tracking number.
 ContentSoftwareId    See section 14. Glossary.

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 Content:
 PackagedContent    Contains actual delivery note information as one
                    or more Packaged Content elements (see section
                    3.7).
 Note: If the content of the Delivery Message is a Mime message then
 the Delivery Note may trigger an application which causes the actual
 delivery to occur.

7.16 Status Component

 A Status Component contains status information about the business
 success or failure (see section 4.2) of a process.
 Its definition is as follows.
 <!ELEMENT Status EMPTY >
 <!ATTLIST Status
  ID                 ID      #REQUIRED
  xml:lang           NMTOKEN #REQUIRED
  StatusType         NMTOKEN #REQUIRED
  ElRef              NMTOKEN #IMPLIED
  ProcessState (NotYetStarted | InProgress |
      CompletedOk | Failed | ProcessError) #REQUIRED
  CompletionCode     NMTOKEN #IMPLIED
  ProcessReference   CDATA   #IMPLIED
  StatusDesc         CDATA   #IMPLIED >
 Attributes:
 ID                 An identifier which uniquely identifies the Status
                    Component within the IOTP Transaction.
 xml:lang           Defines the language used by attributes within
                    this component. See section 3.8 Identifying
                    Languages.
 StatusType         Indicates the type of Document Exchange which the
                    Status is reporting on. It may be set to either
                    Offer, Payment, Delivery, Authentication or
                    Undefined.
                    Undefined means that the type of document exchange
                    could not be identified. This is caused by an
                    error in the initial input message of the
                    exchange.

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                    Values of StatusType are managed under the
                    procedure described in section 12 IANA
                    Considerations which also allows user defined
                    values of StatusType to be defined.
 ElRef              If the StatusType is not set to Undefined then
                    ElRef contains an Element Reference (see section
                    3.5) to the Component for which the Status is
                    being described. It must refer to either:
                     o an Order Component (see section 7.5), if the
                       StatusType is Offer,
                     o a Payment Component (see section 7.9), if the
                       StatusType is Payment, or
                     o a Delivery Component (see section 7.13), if
                       the StatusType is Delivery
                     o an Authentication Request Component (see
                       section 7.2) if the StatusType is
                       Authentication.
 ProcessState       Contains a State Code which indicates the current
                    state of the process being carried out. Valid
                    values for ProcessState are:
                     o NotYetStarted. A Request Block has been
                       received but the process has not yet started
                     o InProgress. Processing of the Request Block
                       has started but it is not yet complete
                     o CompletedOk. The processing of the Request
                       Block has completed successfully without any
                       errors
                     o Failed. The processing of the Request Block
                       has failed because of a Business Error (see
                       section 4.2)
                     o ProcessError. This value is only used when the
                       Status Component is being used in connection
                       with an Inquiry Request Trading Block (see
                       section 8.12). It indicates there was a
                       Technical Error (see section 4.1) in the
                       Request Block which is being processed or some
                       internal processing error.
                    Note that this code reports on the processing of a
                    Request Block. Further, asynchronous processing
                    may occur after the Response Block associated with
                    the Process has been sent.

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 CompletionCode     Indicates how the process completed. Valid values
                    for the CompletionCode are given below together
                    with the conditions when it must be present and
                    indications on when recovery from failures are
                    possible.
                    A CompletionCode is a maximum of 14 characters
                    long.
 ProcessReference   This optional attribute holds a reference for the
                    process whose status is being reported. It may
                    hold the following values:
                     o when StatusType is set to Offer, it should
                       contain the OrderIdentifier from the Order
                       Component
                     o when StatusType is set to Payment, it should
                       contain the PaymentHandlerPayId from the
                       Payment Scheme Data Component
                     o when StatusType is set to Delivery, it should
                       contain the DelivHandlerDelivId from the
                       Delivery Note Component
                     o when StatusType is set to Authentication, it
                       should contain the AuthenticationId from the
                       Authentication Request Component
                    This attribute should be absent in the Inquiry
                    Request message when the Consumer has not been
                    given such a reference number by the IOTP Service
                    Provider.
                    This attribute can be used inside an Inquiry
                    Response Block (see section 8.13) to give the
                    reference number for a transaction which has
                    previously been unavailable.
                    For example, the package tracking number might not
                    be assigned at the time a delivery response was
                    received. However, if the Consumer issues a
                    Baseline Transaction Status Inquiry later, the
                    Delivery Handler can put the package tracking
                    number into this attribute in the Inquiry Response
                    message and send it back to the Consumer.
 StatusDesc         An optional textual description of the current
                    status of the process in the language identified
                    by xml:lang.

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7.16.1 Offer Completion Codes

 The Completion Code is only required if the ProcessState attribute is
 set to Failed. The following table contains the valid values for the
 CompletionCode that may be used and indicates whether or not recovery
 might be possible. It is recommended that the StatusDesc attribute is
 used to provide further explanation where appropriate.
     Value                            Description
 AuthError        Authentication Error. The check of the
                  Authentication Response which was carried out has
                  failed.
                  Recovery may be possible by the Consumer re-
                  submitting a new Authentication Response Block with
                  corrected information.
 ConsCancelled    Consumer Cancelled. The Consumer decides to cancel
                  the transaction for some reason. This code is only
                  valid in a Status Component contained in a Cancel
                  Block or an Inquiry Response Block.
                  No recovery possible.
 MerchCancelled   Offer Cancelled. The Merchant declines to generate
                  an offer for some reason and cancels the
                  transaction. This code is only valid in a Status
                  Component contained in a Cancel Block or an Inquiry
                  Response Block.
                  No recovery possible.
 Unspecified      Unspecified error. There is some unknown problem or
                  error which does not fall into one of the other
                  CompletionCodes.
                  No recovery possible.
 TimedOutRcvr     Recoverable Time Out. Messages were resent but no
                  response received. The document exchange has
                  therefore "Timed Out". This code is only valid on a
                  Transaction Inquiry.
                  Recovery is possible if the last message from the
                  other Trading Role is received again.

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 TimedOutNoRcvr   Non Recoverable Time Out. Messages were resent but
                  no response received. The document exchange has
                  therefore "Timed Out". This code is only valid on a
                  Transaction Inquiry.
                  No recovery possible.

7.16.2 Payment Completion Codes

 The CompletionCode is only required if the ProcessState attribute is
 set to Failed. The following table contains the valid values for the
 CompletionCode that may be used and indicates where recovery may be
 possible. It is recommended that the StatusDesc attribute is used by
 individual payment schemes to provide further explanation where
 appropriate.
       Value                           Description
 BrandNotSupp       Brand not supported. The payment brand is not
                    supported by the Payment Handler.
                    See below for recovery options.
 CurrNotSupp        Currency not supported. The currency in which the
                    payment is to be made is not supported by either
                    the Payment Instrument or the Payment Handler.
                    If the payment is Brand Independent, then the
                    Consumer may recover by selecting a different
                    currency, if available, or a different brand. Note
                    that this may involve a different Payment Handler.
 ConsCancelled      Consumer Cancelled. The Consumer decides to cancel
                    the payment for some reason. This code is only
                    valid in a Status Component contained in a Cancel
                    Block or an Inquiry Response Block.
                    Recovery is not possible.
 PaymtCancelled     Payment Cancelled. The Payment Handler declines to
                    complete the payment for some reason and cancels
                    the transaction. This code is only valid in a
                    Status Component contained in a Cancel Block or an
                    Inquiry Response Block.
                    See below for recovery options.

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 AuthError          Authentication Error. The Payment Scheme specific
                    authentication check which was carried out has
                    failed.
                    Recovery may be possible. See the payment scheme
                    supplement to determine what is allowed.
 InsuffFunds        Insufficient funds. There are insufficient funds
                    available for the payment to be made.
                    See below for recovery options.
 InstBrandInvalid   Payment Instrument not valid for Brand. A Payment
                    Instrument is being used which does not correspond
                    with the Brand selected. For example a Visa credit
                    card is being used when MasterCard was selected as
                    the Brand.
                    See below for recovery options.
 InstNotValid       Payment instrument not valid for trade. The
                    Payment Instrument cannot be used for the proposed
                    type of trade, for some reason.
                    See below for recovery options.
 BadInstrument      Bad instrument. There is a problem with the
                    Payment Instrument being used which means that it
                    is unable to be used for the payment.
                    See below for recovery options.
 Unspecified        Unspecified error. There is some unknown problem
                    or error which does not fall into one of the other
                    CompletionCodes. The StatusDesc attribute should
                    provide the explanation of the cause.
                    See below for recovery options.
 TimedOutRcvr       Recoverable Time Out. Messages were resent but no
                    response received. The document exchange has
                    therefore "Timed Out". This code is only valid on
                    a Transaction Inquiry.
                    Recovery is possible if the last message from the
                    other Trading Role is received again.

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 TimedOutNoRcvr     Non Recoverable Time Out. Messages were resent but
                    no response received. The document exchange has
                    therefore "Timed Out". This code is only valid on
                    a Transaction Inquiry.
                    No recovery possible.
 If the Payment is Brand Independent, then recovery may be possible
 for some values of the Completion Code, by the Consumer selecting
 either a different payment brand or a different payment instrument
 for the same brand. Note that this might involve a different Payment
 Handler. The codes to which this applies are: BrandNotSupp,
 PaymtCancelled, InsuffFunds, InstBrandInvalid, InstNotValid,
 BadInstrument and Unspecified.
 Recovery from Payments associated with Brand Dependent purchases is
 only possible, if the Brand Selection component sent by the Merchant
 to the Consumer does not change. In practice this means that the same
 Brand, Protocol Amount and PayProtocol elements must be used. All
 that can change is the Payment Instrument. Any other change will
 invalidate the Merchant's Offer as a changed selection will
 invalidate the Offer Response.

7.16.3 Delivery Completion Codes

 The following table contains the valid values for the CompletionCode
 attribute for a Delivery. It is recommended that the StatusDesc
 attribute is used to provide further explanation where appropriate.
      Value                           Description
 BackOrdered     Back Ordered. The goods to be delivered are on order
                 but they have not yet been received. Shipping will be
                 arranged when they are received. This is only valid
                 if ProcessState is CompletedOk.
                 Recovery is not possible.
 PermNotAvail    Permanently Not Available. The goods are permanently
                 unavailable and cannot be re-ordered. This is only
                 valid if ProcessState is Failed.
                 Recovery is not possible.
 TempNotAvail    Temporarily Not Available. The goods are temporarily
                 unavailable and may become available if they can be
                 ordered. This is only valid if ProcessState is
                 CompletedOk.

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                 Recovery is not possible.
 ShipPending     Shipping Pending. The goods are available and are
                 scheduled for shipping but they have not yet been
                 shipped. This is only valid if ProcessState is
                 CompletedOk.
                 Recovery is not possible.
 Shipped         Goods Shipped. The goods have been shipped.
                 Confirmation of delivery is awaited. This is only
                 valid if ProcessState is CompletedOk.
                 Recovery is not possible.
 ShippedNoConf   Shipped - No Delivery Confirmation. The goods have
                 been shipped but it is not possible to confirm
                 delivery of the goods. This is only valid if
                 ProcessState is CompletedOk.
                 Recovery is not possible.
 ConsCancelled   Consumer Cancelled. The Consumer decides to cancel
                 the delivery for some reason. This code is only valid
                 in a Status Component contained in a Cancel Block or
                 an Inquiry Response Block.
                 Recovery is not possible.
 DelivCancelled  Delivery Cancelled. The Delivery Handler declines to
                 complete the Delivery for some reason and cancels the
                 transaction. This code is only valid in a Status
                 Component contained in a Cancel Block or an Inquiry
                 Response Block.
                 Recovery is not possible.
 Confirmed       Confirmed. All goods have been delivered and
                 confirmation of their delivery has been received.
                 This is only valid if ProcessState is CompletedOk.
                 Recovery is not possible.
 Unspecified     Unspecified error. There is some unknown problem or
                 error which does not fall into one of the other
                 CompletionCodes. The StatusDesc attribute should
                 provide the explanation of the cause.

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                 Recovery is not possible.
 TimedOutRcvr    Recoverable Time Out. Messages were resent but no
                 response received. The document exchange has
                 therefore "Timed Out". This code is only valid on a
                 Transaction Inquiry.
                 Recovery is possible if the last message from the
                 other Trading Role is received again.
 TimedOutNoRcvr  Non Recoverable Time Out. Messages were resent but no
                 response received. The document exchange has
                 therefore "Timed Out". This code is only valid on a
                 Transaction Inquiry.
                 No recovery possible.
 Note: Recovery from failed, or partially completed deliveries is not
 possible. The Consumer should use the Transaction Status Inquiry
 Transaction (see section 9.2.1) to determine up-to- date information
 on the current state.

7.16.4 Authentication Completion Codes

 The Completion Code is only required if the ProcessState attribute is
 set to Failed. The following table contains the valid values for the
 CompletionCode that may be used. It is recommended that the
 StatusDesc attribute is used to provide further explanation where
 appropriate.
      Value                           Description
 AutEeCancel     Authenticatee Cancel. The Organisation being
                 authenticated declines to be authenticated for some
                 reason. This could be, for example because the
                 signature on an Authentication Request was invalid or
                 the Authenticator was not known or acceptable to the
                 Authenticatee.
                 Recovery is not possible.
 AutOrCancel     Authenticator Cancel. The Organisation requesting
                 authentication declines to validate the
                 Authentication Response received for some reason and
                 cancels the transaction.
                 Recovery is not possible.

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 NoAuthReq       Authentication Request Not Available. The
                 Authenticatee does not have the data that must be
                 provided so that they may be successfully
                 authenticated. For example a password may have been
                 forgotten, the Authenticatee has not yet become a
                 member, or a smart card token is not present.
                 Recovery is not possible
 AuthFailed      Authentication Failed. The Authenticator checked the
                 Authentication Response but the authentication failed
                 for some reason. For example a password may have been
                 incorrect.
                 Recovery may be possible by the Authenticatee re-
                 sending a revised Authentication Response with
                 corrected data.
 TradRolesIncon  Trading Roles Inconsistent. The Trading Roles
                 contained within the TradingRoleList attribute of the
                 Trading Role Information Request Component (see
                 section 7.4) are inconsistent with the Trading Role
                 which the Authenticatee is taking in the IOTP
                 Transaction or is able to take. Examples of
                 inconsistencies include:
                  o asking a PaymentHandler for DeliveryHandler
                   information
                  o asking a Consumer for Merchant information
                 Recovery may be possible by the Authenticator re-
                 sending a revised Authentication Request Block with
                 corrected information.
 Unspecified     Unspecified error. There is some unknown problem or
                 error which does not fall into one of the other
                 CompletionCodes.
                 Recovery is not possible.
 TimedOutRcvr    Recoverable Time Out. Messages were resent but no
                 response received. The document exchange has
                 therefore "Timed Out". This code is only valid on a
                 Transaction Inquiry.
                 Recovery is possible if the last message from the
                 other Trading Role is received again.

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 TimedOutNoRcvr  Non Recoverable Time Out. Messages were resent but no
                 response received. The document exchange has
                 therefore "Timed Out". This code is only valid on a
                 Transaction Inquiry.
                 No recovery possible.

7.16.5 Undefined Completion Codes

 The Completion Code is only required if the ProcessState attribute is
 set to Failed. The following table contains the valid values for the
 CompletionCode that may be used. It is recommended that the
 StatusDesc attribute is used to provide further explanation where
 appropriate.
      Value                           Description
 InMsgHardError  Input Message Hard Error. The type of Request Block
                 could not be identified or was inconsistent.
                 Therefore no single Document Exchange could be
                 identified. This will cause a Hard Error in the
                 transaction

7.16.6 Transaction Inquiry Completion Codes

 The Completion Code is only required if the ProcessState attribute is
 set to Failed. The following table contains the valid values for the
 CompletionCode that may be used. It is recommended that the
 StatusDesc attribute is used to provide further explanation where
 appropriate.
      Value                           Description
 UnAuthReq       Unauthorised Request. The recipient of the
                 Transaction Status Request declines to respond to the
                 request.

7.17 Trading Role Data Component

 The Trading Role Data Component contains opaque data which needs to
 be communicated between the Trading Roles involved in an IOTP
 Transaction.
 Trading Role Components identify:
 o the Organisation that generated the component, and
 o the Organisation that is to receive it.

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 They are first generated and included in a "Response" Block, and then
 copied to the appropriate "Request" Block. For example a Payment
 Handler might need to inform a Delivery Handler that a credit card
 payment had been authorised but not captured. There may also be other
 information that the Payment Handler has generated where the format
 is privately agreed with the Delivery Handler which needs to be
 communicated. In another example a Merchant might need to provide a
 Payment Handler with some specific information about a Consumer so
 that consumer can acquire double loyalty points with the payment.
 Its definition is as follows.
 <!ELEMENT TradingRoleData (PackagedContent+) >
 <!ATTLIST TradingRoleData
   ID                ID      #REQUIRED
   OriginatorElRef   NMTOKEN #REQUIRED
   DestinationElRefs NMTOKENS #REQUIRED >
 Attributes:
 ID                 An identifier which uniquely identifies the
                    Trading Role Data Component within the IOTP
                    Transaction.
 OrginatorElRef     Contains an element reference to the Organisation
                    Component of the Organisation that created the
                    Trading Role Data Component and included it in a
                    "Response" Block (e.g., an Offer Response or a
                    Payment Response Block).
 DestinationElRefs  Contains element references to the Organisation
                    Components of the Organisations that are to
                    receive the Trading Role Data Component in a
                    "Request" Block (e.g., either a Payment Request or
                    a Delivery Request Block).
 Content:
 PackagedContent    This contains the data which is to be sent between
                    the various Trading Roles as one or more
                    PackagedContent elements see section 3.7.

7.17.1 Who Receives a Trading Role Data Component

 The rules for deciding what to do with Trading Role Data Components
 are described below.

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 o  whenever a Trading Role Data Component is received in a "Response"
    block identify the Organisation Components of the Organisations
    that are to receive it as identified by the DestinationElRefs
    attribute.
 o  whenever a "Request" Block is being sent, check to see if it is
    being sent to one of the Organisations identified by the
    DestinationElRefs attribute. If it is then include in the
    "Request" block:
  1. the Trading Role Data Component as well as,
  1. the Organisation Component of the Organisation identified by

the OriginatorElRef attribute (if not already present)

7.18 Inquiry Type Component

 The Inquiry Type Component contains the information which indicates
 the type of process that is being inquired upon. Its definition is as
 follows.
 <!ELEMENT InquiryType EMPTY >
 <!ATTLIST InquiryType
  ID                 ID      #REQUIRED
  Type               NMTOKEN #REQUIRED
  ElRef              NMTOKEN #IMPLIED
  ProcessReference   CDATA   #IMPLIED >
 Attributes:
 ID                 An identifier which uniquely identifies the
                    Inquiry Type Component within the IOTP
                    Transaction.
 Type               Contains the type of inquiry. Valid values for
                    Type are:
                     o Offer. The inquiry is about the status of an
                       offer and is addressed to the Merchant.
                     o Payment. The inquiry is about the status of a
                       payment and is addressed to the Payment
                       Handler.
                     o Delivery. The inquiry is about the status of a
                       delivery and addressed to the Delivery Handler.
 ElRef              Contains an Element Reference (see section 3.5) to
                    the component to which this Inquiry Type Component
                    applies. That is,
                     o TPO Block when Type is Offer

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                     o Payment Component when Type is Payment
                     o Delivery Component when Type is Delivery
 ProcessReference   Optionally contains a reference to the process
                    being inquired upon. It should be set if the
                    information is available. For the definition of
                    the values it may contain, see the
                    ProcessReference attribute of the Status Component
                    (see section 7.16).

7.19 Signature Component

 Note: Definitions of the XML structures for signatures and
 certificates are described in the document titled "Digital Signatures
 for the Internet Open Trading Protocol" by Kent Davidson and Yoshiaki
 Kawatsura published at the same time as this document - see
 [IOTPDSIG].
 In the future it is anticipated that future versions of IOTP will
 adopt a whatever method for digitally signing XML becomes the
 standard.
 Each Signature Component digitally signs one or more Blocks or
 Components including other Signature Components.
 The Signature Component:
 o  contains digests of one or more Blocks or Components in one or
    more IOTP Messages within the same IOTP Transaction and places the
    result in a Digest Element
 o  concatenates these Digest elements with other information on the
    type of signature, the originator and potential recipients of the
    signature and details of the signature algorithms being used and
    places them in a Manifest element, and
 o  signs the Manifest element using the optional certificate
    identified in the Certificate element within the Signature Block
    placing the result in a Value element within a Signature Component
 Note that there may be multiple Value elements that contain
 signatures of a Manifest Element.
 A Signature Component can be one of four types either:
 o an Offer Response Signature,
 o a Payment Response Signature,

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 o a Delivery Response Signature, or
 o an Authentication Response Signature.
 For a general explanation of signatures see section 6 Digital
 Signatures.

7.19.1 IOTP usage of signature elements and attributes

 Definitions of the elements and attributes are contained in
 [IOTPDSIG].  The following contains additional information that
 describes how these elements and attributes are used by IOTP.
 SIGNATURE ELEMENT
 The ID attribute is mandatory.
 MANIFEST ELEMENT
 The optional LocatorHrefBase attribute contains text which should be
 concatenated before the text contained in the LocatorHREF attribute
 of all Digest elements within the Manifest.
 Its purpose is to reduce the size of LocatorHREF attribute values
 since the first part of the LocatorHREF attributes in the same
 signature are likely to be the same.
 Typically, within IOTP, it will contain all the characters in a
 LocatorHref attribute up to the sharp ("#") character (see
 immediately below).
 ALGORITHM AND PARAMETER ELEMENTS
 The algorithm element identifies the algorithms used in generating
 the signature. The type of the algorithm is defined by the value of
 the Type attribute which indicates if it is to be used as a Digest
 algorithm, a Signature algorithm or a Key Agreement algorithm.
 The following Digest algorithms must be implemented:
 o  a [DOM-HASH] algorithm. This is identified by setting the Name
    attribute of the Algorithm element to "urn:ibm:dom-hash"
 o  a [SHA1] algorithm. This is identified by setting the Name
    attribute of the Algorithm element to "urn:fips:sha1", and
 o  a [MD5] algorithm. This is identified by setting the Name
    attribute of the Algorithm element to "urn:rsa:md5"

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 o  The following Signature algorithms must be implemented:
 o  a [DSA] algorithm. This is identified by setting the Name
    attribute of the Algorithm element to "urn:us.gov:dsa"
 o  a [HMAC] algorithm. This is identified by setting the Name
    attribute of the Algorithm element to "urn:ibm:hmac"
 It is recommended that the following Signature algorithm is also
 implemented:
 o  a [RSA] algorithm. This is identified by setting the Name
    attribute of the Algorithm element to "urn:rsa:rsa"
 In addition other payment scheme specific algorithms may be used. In
 this case the value of the name attribute to use is specified in the
 payment scheme supplement for that algorithm.
 One algorithm may make use of other algorithms by use of the
 Parameter element, for example:
 <Algorithm ID=A1 type="digest" name="urn:ibm:dom-hash">
   <Parameter type='AlgorithmRef'>A2</Parameter>
 </Algorithm>
 <Algorithm ID=A2 type="digest" name="urn:fips:sha1">
 </Algorithm>
 <Algorithm ID=A3 type="signature" name="urn:ibm:hmac">
     <Parameter type='AlgorithmRef'>A1</Parameter>
 </Algorithm>
 DIGEST ELEMENT
 The LocatorHREF attribute identifies the IOTP element which is being
 digitally signed. Specifically it consists of:
 o  the value of the IotpTransId attribute of the Transaction ID
    Component, followed by:
 o  a sharp character, i.e. "#", followed by
 o  an Element Reference (see section 3.5) to the element within the
    IOTP Transaction which is the subject of the digest.
 Before analysing the structure of the LocatorHREF attribute, it must
 be concatenated with the value of the LocatorHrefBase attribute of
 the Manifest element (see immediately above).

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 ATTRIBUTE ELEMENT
 There must be one and only one Attribute Element that contains a Type
 attribute with a value of IOTP Signature Type and with content set to
 either: OfferResponse, PaymentResponse, DeliveryResponse,
 AuthenticationRequest, AuthenticationResponse, PingRequest or
 PingResponse; depending on the type of the signature.
 Values of the content of the Attribute element are controlled under
 the procedures defined in section 12 IANA Considerations which also
 allows user defined values to be defined.
 The Critical attribute must be set to true.
 ORIGINATORINFO ELEMENT
 The OriginatorRef attribute of the OriginatorInfo element must always
 be present and contain an Element Reference (see section 3.5) to the
 Organisation Component of the Organisation that generated the
 Signature Component.
 RECIPIENTINFO ELEMENT
 The RecipientRefs attribute contains a list of Element References
 (see section 3.5), that point to the Organisations that might need to
 validate the signature. For details see below.

7.19.2 Offer Response Signature Component

 The Manifest Element of a signature which has a type of OfferResponse
 should contain Digest elements for the following Components:
 o  the Transaction Id Component (see section 3.3.1) of the IOTP
    message that contains the Offer Response Signature
 o  the Transaction Reference Block (see section 3.3) of the IOTP
    Message that contains the Offer Response Signature
 o  from the TPO Block:
  1. the Protocol Options Component
  1. each of the Organisation Components
  1. each of the Brand List Components

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 o  optionally, all the Brand Selection Components if they were sent
    to the Merchant in a TPO Selection Block
 o  from the Offer Response Block:
  1. the Order Component
  1. each of the Payment Components
  1. the Delivery Component
  1. each of the Authentication Request Components
  1. any Trading Role Data Components
 The Offer Response Signature should also contain Digest elements for
 the components that describe each of the Organisations that may or
 will need to verify the signature. This involves:
 o  if the Merchant has received a TPO Selection Block containing
    Brand Selection Components, then generate a Digest element for the
    Payment Handler identified by the Brand Selection Component and
    the Delivery Handler identified by the Delivery Component. See
    section 6.3.1 Check Request Block sent Correct Organisation for a
    description of how this can be done.
 o  if the Merchant is not expecting to receive a TPO Selection Block
    then generate a Digest element for the Delivery Handler and all
    the Payment Handlers that are involved.

7.19.3 Payment Receipt Signature Component

 The Manifest Element of the Payment Receipt Signature Component
 should contain Digest Elements for the following Components:
 o  the Transaction Id Component (see section 3.3.1) of the IOTP
    message that contains the Payment Receipt Signature
 o  the Transaction Reference Block (see section 3.3) of the IOTP
    Message that contains the Payment Receipt Signature
 o  the Offer Response Signature Component
 o  the Payment Receipt Component
 o  the Payment Note Component
 o  the Status Component

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 o  the Brand Selection Component.
 o  any Trading Role Data Components

7.19.4 Delivery Response Signature Component

 The Manifest Element of the Delivery Response Signature Component
 should contain Digest Elements for the following Components:
 o  the Transaction Id Component (see section 3.3.1) of the IOTP
    message that contains the Delivery  Response Signature
 o  the Transaction Reference Block (see section 3.3) of the IOTP
    Message that contains the Delivery Response Signature
 o  the Consumer Delivery Data component contained in the preceding
    Delivery Request (if any)
 o  the Signature Components contained in the preceding Delivery
    Request (if any)
 o  the Status Component
 o  the Delivery Note Component

7.19.5 Authentication Request Signature Component

 The Manifest Element of the Authentication Request Signature
 Component should contain Digest Elements for the following
 Components:
 o  the Transaction Reference Block (see section 3.3) for the IOTP
    Message that contains information that describes the IOTP Message
    and IOTP Transaction
 o  the Transaction Id Component (see section 3.3.1) which globally
    uniquely identifies the IOTP Transaction
 o  the following components of the TPO Block :
  1. the Protocol Options Component
  1. the Organisation Component
 o  the following components of the Authentication Request Block:
  1. the Authentication Request Component(s) (if present)

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  1. the Trading Role Information Request Component (if present)

7.19.6 Authentication Response Signature Component

 The Manifest Element of the Authentication Response Signature
 Component should contain Digest Elements for the following
 Components:
 o  the Transaction Reference Block (see section 3.3) for the IOTP
    Message that contains information that describes the IOTP Message
    and IOTP Transaction
 o  the Transaction Id Component (see section 3.3.1) which globally
    uniquely identifies the IOTP Transaction
 o  the following components of the Authentication Request Block:
  1. the Authentication Request Component that was used in the

Authentication (if present)

  1. the Trading Role Information Request Component (if present)
 o  the Organisation Components contained in the Authentication
    Response Block

7.19.7 Inquiry Request Signature Component

 If the Inquiry Request is being signed (see section 9.2.1) the
 Manifest Element of the Inquiry Request Signature Component should
 contain Digest elements of the Inquiry Type Component, and if
 present, the Payment Scheme Component.

7.19.8 Inquiry Response Signature Component

 If the Inquiry Response is being signed (see section 9.2.1) the
 Manifest Element of the Inquiry Response Signature Component should
 contain Digest elements of the Trading Response Block and the Status
 Component.

7.19.9 Ping Request Signature Component

 If the Ping Request is being singed (see section 9.2.2), the Manifest
 Element of the Ping Request Signature Component should contain Digest
 elements for all the Organisation Components.

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7.19.10 Ping Response Signature Component

 If the Ping Response is being singed (see section 9.2.2), the
 Manifest Element of the Ping Response Signature Component should
 contain Digest elements fir all the Organisation Components.

7.20 Certificate Component

 Note: Definitions of the XML structures for signatures and
 certificates are described in the paper "Digital Signatures for the
 Internet Open Trading Protocol", see [IOTPDSIG].
 See note at the start of section 7.19 Signature Component for more
 details.
 A Certificate Component contains a Digital Certificate. They are used
 only when required, for example, when asymmetric cryptography is
 being used and the recipient of the signature that needs to check has
 not already received the Public Key.
 The structure of a Certificate Component is defined in [IOTPDSIG].

7.20.1 IOTP usage of signature elements and attributes

 Detailed definitions of the above elements and attributes are
 contained in [IOTPDSIG]. The following contains additional
 information that describes how these elements and attributes are used
 by IOTP.
 CERTIFICATE COMPONENT
 The ID attribute is mandatory.
 VALUE ELEMENT
 The ID attribute is mandatory.

7.21 Error Component

 The Error Component contains information about Technical Errors (see
 section 4.1) in an IOTP Message which has been received by one of the
 Trading Roles involved in the trade.
 For clarity two phrases are defined which are used in the description
 of an Error Component:
 o  message in error. An IOTP message which contains or causes an
    error of some kind

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 o  message reporting the error. An IOTP message that contains an
    Error Component that describes the error found in a message in
    error.
 The definition of the Error Component is as follows.
 <!ELEMENT ErrorComp (ErrorLocation+, PackagedContent*) >
 <!ATTLIST ErrorComp
  ID                 NMTOKEN #REQUIRED
  xml:lang           NMTOKEN #REQUIRED
  ErrorCode          NMTOKEN #REQUIRED
  ErrorDesc          CDATA   #REQUIRED
  Severity (Warning|TransientError|HardError) #REQUIRED
  MinRetrySecs       CDATA   #IMPLIED
  SwVendorErrorRef   CDATA   #IMPLIED >
 Attributes:
 ID                 An identifier which uniquely identifies the Error
                    Component within the IOTP Transaction.
 xml:lang           Defines the language used by attributes or child
                    elements within this component, unless overridden
                    by an xml:lang attribute on a child element. See
                    section 3.8 Identifying Languages.
 ErrorCode          Contains an error code which indicates the nature
                    of the error in the message in error. Valid values
                    for the ErrorCode are given in section 7.21.2
                    Error Codes.
 ErrorDesc          Contains a narrative description of the error in
                    the language defined by xml:lang. The content of
                    this attribute is defined by the vendor/developer
                    of the software which generated the Error
                    Component
 Severity           Indicates the severity of the error.  Valid values
                    are:
                     o Warning. This indicates that although there is
                       a message in error the IOTP Transaction can
                       still continue.
                     o TransientError. This indicates that the error
                       in the message in error may be recovered if the
                       message in error  that is referred to by the
                       ErrorLocation element is resent

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                     o HardError. This indicates that there is an
                       unrecoverable error in the message in error and
                       the IOTP Transaction must stop.
 MinRetrySecs       This attribute should be present if Severity is
                    set to TransientError. It is the minimum number of
                    whole seconds which the IOTP aware application
                    which received the message reporting the error
                    should wait before re-sending the message in error
                    identified by the ErrorLocation element.
                    If Severity is not set to TransientError then the
                    value of this attribute is ignored.
 SwVendorErrorRef   This attribute is a reference whose value is set
                    by the vendor/developer of the software which
                    generated the Error Component. It should contain
                    data which enables the vendor to identify the
                    precise location in their software and the set of
                    circumstances which caused the software to
                    generate a message reporting the error. See also
                    the SoftwareId attribute of the Message Id element
                    in the Transaction Reference Block (section 3.3).
 Content:
 ErrorLocation      This identifies the IOTP Transaction Id of the
                    message in error  and, where possible, the element
                    and attribute in the message in error that caused
                    the Error Component to be generated.
                    If the Severity of the error is not
                    TransientError, more than one ErrorLocation may be
                    specified as appropriate depending on the nature
                    of the error (see section 7.21.2 Error Codes) and
                    at the discretion of  the vendor/developer of the
                    IOTP Aware Application.
 PackagedContent    This contains additional data which can be used to
                    understand the error. Its content may vary as
                    appropriate depending on the nature of the error
                    (see section 7.21.2 Error Codes) and at the
                    discretion of the vendor/developer of the IOTP
                    Aware Application. For a definition of
                    PackagedContent see section 3.7.

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7.21.1 Error Processing Guidelines

 If there is more than one Error Component in a message reporting the
 error, carry out the actions appropriate for the Error Component with
 the highest severity. In this context, HardError has a higher
 severity than TransientError, which has a higher severity than
 Warning.

7.21.1.1 Severity - Warning

 If an IOTP aware application is generating a message reporting the
 error with an Error Component where the Severity attribute is set to
 Warning, then if the message reporting the error does not contain
 another Error Component with a severity higher than Warning, the IOTP
 Message must also include the Trading Blocks and Trading Components
 that would have been included if no error was being reported.
 If a message reporting the error is received with an Error Component
 where Severity is set to Warning, then:
 o  it is recommended that information about the error is either
    logged, or otherwise reported to the user,
 o  the implementer of the IOTP aware application must either, at
    their or the user's discretion:
  1. continue the IOTP transaction as normal, or
  1. fail the IOTP transaction by generating a message reporting the

error with an Error Component with Severity set to HardError

       (see section 7.21.1.3).
 If the intention is to continue the IOTP transaction then, if there
 are no other Error Components with a higher severity, check that the
 necessary Trading Blocks and Trading Components for normal processing
 of the transaction to continue are present. If they are not then
 generate a message reporting the error with an Error Component with
 Severity set to HardError.

7.21.1.2 Severity - Transient Error

 If an IOTP Aware Application is generating a message reporting the
 error with an Error Component where the Severity attribute is set to
 TransientError, then there should be only one Error Component in the
 message reporting the error. In addition, the MinRetrySecs attribute
 should be present.

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 If a message reporting the error is received with an Error Component
 where Severity is set to TransientError then:
 o  if the MinRetrySecs attribute is present and a valid number, then
    use the MinRetrySecs value given. Otherwise if MinRetrySecs is
    missing or is invalid, then:
  1. generate a message reporting the error containing an Error

Component with a Severity of Warning and send it on the next

       IOTP message (if any) to be sent to the Trading Role which sent
       the message reporting the error with the invalid MinRetrySecs,
       and
  1. use a value for MinRetrySecs which is set by the

vendor/developer of the IOTP Aware Application.

 o  check that only one ErrorLocation element is contained within the
    Error Component and that it refers to an IOTP Message which was
    sent by the recipient of the Error Component with a Severity of
    TransientError. If more than one ErrorLocation is present then
    generate a message reporting the error with a Severity of
    HardError.

7.21.1.3 Severity - Hard Error

 If an IOTP Aware Application is generating a message reporting the
 error with an Error Component where the Severity attribute set to
 HardError, then there should be only one Error Component in the
 message reporting the error.
 If a message reporting the error is received with an Error Component
 where Severity is set to HardError then terminate the IOTP
 Transaction.

7.21.2 Error Codes

 The following table contains the valid values for the ErrorCode
 attribute of the Error Component. The first sentence of the
 description contains the text that should be used to describe the
 error when displayed or otherwise reported. Individual
 implementations may translate this into alternative languages at
 their discretion.
 An Error Code must not be more that 14 characters long.

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      Value                           Description
 Reserved        Reserved. This error is reserved by the
                 vendor/developer of the software. Contact the
                 vendor/developer of the software for more information
                 See the SoftwareId attribute of the Message Id
                 element in the Transaction Reference Block(section
                 3.3).
 XmlNotWellFrmd  XML not well formed. The XML document is not well
                 formed. See [XML] for the meaning of "well formed".
                 Even if the XML is not well formed, it should still
                 be scanned to find the Transaction Reference Block so
                 that a properly formed Error Response may be
                 generated.
 XmlNotValid     XML not valid. The XML document is well formed but
                 the document is not valid. See [XML] for the meaning
                 of "valid". Specifically:
                  o the XML document does not comply with the
                   constraints defined in the IOTP document type
                   declaration (DTD) (see section 13 Internet Open
                   Trading Protocol Data Type Definition), and
                  o the XML document does not comply with the
                   constraints defined in the document type
                   declaration of any additional [XML Namespace] that
                   are declared.
                 As for XML not well formed, attempts should still be
                 made to extract the Transaction Reference Block so
                 that a properly formed Error Response may be
                 generated.
 ElUnexpected    Unexpected element. Although the XML document is well
                 formed and valid, an element is present that is not
                 expected in the particular context according to the
                 rules and constraints contained in this
                 specification.
 ElNotSupp       Element not supported. Although the document is well
                 formed and valid, an element is present that:
                  o is consistent with the rules and constraints
                   contained in this specification, but
                  o is not supported by the IOTP Aware Application
                   which is processing the IOTP Message.

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 ElMissing       Element missing. Although the document is well formed
                 and valid, an element is missing that should have
                 been present if the rules and constraints contained
                 in this specification are followed.
                 In this case set the PackagedContent of the Error
                 Component to the type of the missing element.
 ElContIllegal   Element content illegal. Although the document is
                 well formed and valid, the element Content contains
                 values which do not conform to the rules and
                 constraints contained in this specification.
 EncapProtErr    Encapsulated protocol error. Although the document is
                 well formed and valid, the PackagedContent of an
                 element contains data from an encapsulated protocol
                 which contains errors.
 AttUnexpected   Unexpected attribute. Although the XML document is
                 well formed and valid, the presence of the attribute
                 is not expected in the particular context according
                 to the rules and constraints contained in this
                 specification.
 AttNotSupp      Attribute not supported. Although the XML document is
                 well formed and valid, and the presence of the
                 attribute in an element is consistent with the rules
                 and constraints contained in this specification, it
                 is not supported by the IOTP Aware Application which
                 is processing the IOTP Message.
 AttMissing      Attribute missing. Although the document is well
                 formed and valid, an attribute is missing that should
                 have been present if the rules and constraints
                 contained in this specification are followed.
                 In this case set the PackagedContent of the Error
                 Component to the type of the missing attribute.
 AttValIllegal   Attribute value illegal. The attribute contains a
                 value which does not conform to the rules and
                 constraints contained in this specification.
 AttValNotRecog  Attribute Value Not Recognised. The attribute
                 contains a value which the IOTP Aware Application
                 generating the message reporting the error could not
                 recognise.

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 MsgTooLarge     Message too large. The message is too large to be
                 processed by the IOTP Aware Application.
 ElTooLarge      Element too large. The element is too large to be
                 processed by the IOTP Aware Application
 ValueTooSmall   Value too small or early. The value of all or part of
                 the Content of an element or an attribute, although
                 valid, is too small.
 ValueTooLarge   Value too large or in the future. The value of all or
                 part of the Content of an element or an attribute,
                 although valid, is too large.
 ElInconsistent  Element Inconsistent. Although the document is well
                 formed and valid, according to the rules and
                 constraints contained in this specification:
                  o the content of an element is inconsistent with the
                   content of other elements or their attributes, or
                  o the value of an attribute is inconsistent with the
                   value of one or more other attributes.
                 In this case create ErrorLocation elements which
                 identify all the attributes or elements which are
                 inconsistent.
 TransportError  Transport Error. This error code is used to indicate
                 that there is a problem with the Transport Mechanism
                 which is preventing the message from being received.
                 It is typically associated with a Transient Error.
                 Explanation of the Transport Error is contained
                 within the ErrorDesc attribute. The values which can
                 be used inside ErrorDesc with a TransportError is
                 specified in the IOTP supplement for the Transport
                 mechanism.
 MsgBeingProc    Message Being Processed. This error code is only used
                 with a Severity of Transient Error. It indicates that
                 the previous message, which may be an exchange
                 message or a request message, is being processed and,
                 if no response is received by the time indicated by
                 the MinRetrySecs attribute, then the original message
                 should be resent.
 SystemBusy      System Busy. This error code is only used with a
                 Severity of Transient Error. It indicates that the
                 server that received a message is currently too busy
                 to handle the message. If no response is received by

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                 the time indicated by the MinRetrySecs attribute,
                 then the original message should be resent.
 Note: If the server/system handling the Transport Mechanism (e.g.,
 HTTP) is busy then a Transport Specific error message should be used
 instead of an IOTP Error message. This code should be used in
 association with IOTP servers/systems or other servers/systems to
 which the IOTP server is connected.
 UnknownError    Unknown Error. Indicates that the transaction cannot
                 complete for some reason that is not covered
                 explicitly by any of the other errors.  The ErrorDesc
                 attribute should be used to indicate the nature of
                 the problem.
                 This could be used to indicate, for example, an
                 internal error in a backend server or client process
                 of some kind.

7.21.3 Error Location Element

 An Error Location Element identifies an element and optionally an
 attribute in the message in error which is associated with the error.
 It contains a reference to the IOTP Message, Trading Block, Trading
 Component, element and attribute, which is in error.
 <!ELEMENT ErrorLocation EMPTY >
 <!ATTLIST ErrorLocation
  ElementType        NMTOKEN #REQUIRED
  IotpMsgRef         NMTOKEN #IMPLIED
  BlkRef             NMTOKEN #IMPLIED
  CompRef            NMTOKEN #IMPLIED
  ElementRef         NMTOKEN #IMPLIED
  AttName            NMTOKEN #IMPLIED >
 Attributes:
 ElementType        This is the name of the type of the element where
                    the error is located. For example if the element
                    was declared as <!ELEMENT Org ... then its name is
                    "Org".
 IotpMsgRef         This is the value of the ID attribute of the of
                    the Message Id Component (see section 3.3.2) of
                    the message in error to which this Error Component
                    applies.

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 BlkRef             If the error is associated with a specific Trading
                    Block, then this is the value of the ID attribute
                    of the Trading Block where the error is located.
 CompRef            If the error is associated with a specific Trading
                    Component, then this is the value of the ID
                    attribute of the Trading Component where the error
                    is located.
 ElementRef         If the error is associated with a specific element
                    within a Trading Component then, if the element
                    has an attribute with an "attribute type" (see
                    [XML]) of "ID", then this is the value of that
                    attribute.
 AttName            If the error is associated with the value of an
                    attribute, then this is the name of that
                    attribute. In this case the PackagedContent of the
                    Error Component should contain the value of the
                    attribute.
 Note that as many as the attributes as possible should be included.
 For example if an attribute in a child element of a Trading Component
 contains an incorrect value, then all the attributes of ErrorLocation
 should be present.

8. Trading Blocks

 Trading Blocks are child elements of the top level IOTP Messages that
 are sent in the form of [XML] documents directly between the
 different Trading Roles that are taking part in a trade.
 Each Trading Blocks consist of one or more Trading Components (see
 section 7).  This is illustrated in the diagram below.

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  • +*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*
           IOTP MESSAGE  <-----------IOTP Message - an XML Document
            |                        which is transported between the
            |                        Trading Roles
            |-Trans Ref Block <----- Trans Ref Block - contains
            |  |                     information which describes the
            |  |                     IOTP Transaction and the IOTP
            |  |                     Message.
            |  |-Trans Id Comp. <--- Transaction Id Component -
            |  |                     uniquely identifies the IOTP
            |  |                     Transaction. The Trans Id
            |  |                     Components are the same across
            |  |                     all IOTP messages that comprise a
            |  |                     single IOTP transaction.
            |  |-Msg Id Comp. <----- Message Id Component - identifies
            |                        and describes an IOTP Message
            |                        within an IOTP Transaction
            |-Signature Block <----- Signature Block (optional) -
            |  |                     contains one or more Signature
            |  |                     Components and their associated
            |  |                     Certificates
            |  |-Signature Comp. <-- Signature Component - contains
            |  |                     digital signatures. Signatures
            |  |                     may sign digests of the Trans Ref
            |  |                     Block and any Trading Component
            |  |                     in any IOTP Message in the same
            |  |                     IOTP Transaction.
            |  |-Certificate Comp. <-Certificate Component. Used to
            |                        check the signature. (Optional)
    ------> |-Trading Block <--------Trading Block - an XML Element
   |        |  |-Trading Comp.       within an IOTP Message that
 Trading    |  |-Trading Comp.       contains a predefined set of
 Blocks     |  |-Trading Comp.       Trading Components
   |        |  |-Trading Comp.
   |        |  |-Trading Comp. <-----Trading Components - XML Elements
   |        |                        within a Trading Block that
    ------> |-Trading Block          contain a predefined set of XML
            |  |-Trading Comp.       elements and attributes
            |  |-Trading Comp.       containing information required
            |  |-Trading Comp.       to support a Trading Exchange
            |  |-Trading Comp.
            |  |-Trading Comp.
            |
 *-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*
                          Figure 16 Trading Blocks

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 Trading Blocks are defined as part of the definition of an IOTP
 Message (see section 3.1.1). The definition of an IOTP Message
 element is repeated here:
 <!ELEMENT IotpMessage
    ( TransRefBlk,
      SigBlk?,
      ErrorBlk?,
      ( AuthReqBlk |
        AuthRespBlk |
        AuthStatusBlk |
        CancelBlk |
        DeliveryReqBlk |
        DeliveryRespBlk |
        InquiryReqBlk |
        InquiryRespBlk |
        OfferRespBlk |
        PayExchBlk |
        PayReqBlk |
        PayRespBlk |
        PingReqBlk |
        PingRespBlk |
        TpoBlk |
        TpoSelectionBlk
      )*
    ) >
 The remainder of this section defines the Trading Blocks in this
 version of IOTP. They are:
 o  Authentication Request Block
 o  Authentication Response Block
 o  Authentication Status Block
 o  Cancel Block
 o  Delivery Request Block
 o  Delivery Response Block
 o  Error Block
 o  Inquiry Request Block
 o  Inquiry Response Block

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 o  Offer Response Block
 o  Payment Exchange Block
 o  Payment Request Block
 o  Payment Response Block
 o  Signature Block
 o  Trading Protocol Options Block
 o  TPO Selection Block
 The Transaction Reference Block is described in section 3.3.

8.1 Trading Protocol Options Block

 The TPO Trading Block contains options which apply to the IOTP
 Transaction. The definition of a TPO Trading Block is as follows.
 <!ELEMENT TpoBlk ( ProtocolOptions, BrandList*, Org* ) >
 <!ATTLIST TpoBlk
  ID                 ID      #REQUIRED >
 Attributes:
 ID                 An identifier which uniquely identifies the
                    Trading Protocol Options Block within the IOTP
                    Transaction (see section 3.4 ID Attributes).
 Content:
 ProtocolOptions    The Protocol Options Component (see section
                    7.1)defines the options which apply to the whole
                    IOTP Transaction (see section 9).
 BrandList          This Brand List Component contains one or more
                    payment brands and protocols which may be selected
                    (see section 7.7).
 Org                The Organisation Components (see section 7.6)
                    identify the Organisations and their roles in the
                    IOTP Transaction. The roles and Organisations
                    which must be present will depend on the
                    particular type of IOTP Transaction. See the
                    definition of each transaction in section 9.
                    Internet Open Trading Protocol Transactions.

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 The TPO Block should contain:
 o  the Protocol Options Component
 o  the Organisation Component with the Trading Role of Merchant
 o  the Organisation Component with the Trading Role of Consumer
 o  optionally, the Organisation Component with the Trading Role of
    DeliverTo, if there is a Delivery included in the IOTP Transaction
 o  Brand List Components for each payment in the IOTP Transaction
 o  Organisation Components for all the Payment Handlers involved
 o  optionally, Organisation Components for the Delivery Handler (if
    any) for the transaction
 o  additional Organisation Components that the Merchant may want to
    include. For example
  1. a Customer Care Provider
  1. an Certificate Authority that offers Merchant "Credentials" or

some other warranty on the goods or services being offered.

8.2 TPO Selection Block

 The TPO Selection Block contains the results of selections made from
 the options contained in the Trading Protocol Options Block (see
 section 8.1).The definition of a TPO Selection Block is as follows.
 <!ELEMENT TpoSelectionBlk (BrandSelection+) >
 <!ATTLIST TpoSelectionBlk
  ID                 ID      #REQUIRED >
 Attributes:
 ID                 An identifier which uniquely identifies the TPO
                    Selection Block within the IOTP Transaction.
 Content:
 BrandSelection     This identifies the choice of payment brand and
                    payment protocol to be used in a payment within
                    the IOTP Transaction. There is one Brand Selection
                    Component (see section 7.8) for each payment to be
                    made in the IOTP Transaction.

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 The TPO Selection Block should contain one Brand Selection Component
 for each Brand List in the TPO Block.

8.3 Offer Response Block

 The Offer Response Block contains details of the goods, services,
 amount, delivery instructions or financial transaction which is to
 take place.  Its definition is as follows.
 <!ELEMENT OfferRespBlk (Status, Order?, Payment*,
              Delivery?, TradingRoleData*) >
 <!ATTLIST OfferRespBlk
  ID                 ID      #REQUIRED >
 Attributes:
 ID                 An identifier which uniquely identifies the Offer
                    Response Block within the IOTP Transaction.
 Content:
 Status             Contains status information about the business
                    success (see section 4.2) or failure of the
                    generation of the Offer. Note that in an Offer
                    Response Block, a ProcessState of NotYetStarted or
                    InProgress are illegal values.
 Order              The Order Component contains details about the
                    goods, services or financial transaction which is
                    taking place see section 7.5.
                    The Order Component must be present unless the
                    ProcessState attribute of the Status Component is
                    set to Failed.
 Payment            The Payment Components contain information about
                    the payments which are to be made see section 7.9.
 Delivery           The Delivery Component contains details of the
                    delivery to be made (see section 7.13).
 TradingRoleData    The Trading Role Data Component contains opaque
                    data which is needs to be communicated between the
                    Trading Roles involved in an IOTP Transaction (see
                    section 7.17).
 The Offer Response Block should contain:

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 o  the Order Component for the IOTP Transaction
 o  Payment Components for each Payment in the IOTP Transaction
 o  the Delivery Component the IOTP Transaction requires (if any).

8.4 Authentication Request Block

 The Authentication Request Block contains the data which is used by
 one Trading Role to obtain information about and optionally
 authenticate another Trading Role.
 In outline it contains:
 o  information about how the authentication itself will be carried
    out, and/or
 o  a request for additional information about the Organisation being
    authenticated.
 Its definition is as follows.
 <!ELEMENT AuthReqBlk (AuthReq*, TradingRoleInfoReq?) >
 <!ATTLIST AuthReqBlk
  ID                 ID      #REQUIRED >
 Attributes:
 ID                 An identifier which uniquely identifies the
                    Authentication Request Block within the IOTP
                    Transaction.
 Content:
 AuthReq             Each Authentication Request (see section 7.2)
                     component describes an alternative way in which
                     the recipient of the Authentication Request may
                     authenticate themselves by generating an
                     Authentication Response Component (see section
                     7.3).
                     If one Authentication Request Component is
                     present then that Authentication Request
                     Component should be used.

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                     If more than one Authentication Request Component
                     is present then the recipient should choose one
                     of the components based on personal preference of
                     the recipient or their software.
                     If no Authentication Request Component is present
                     it means that the Authentication Request Block is
                     requesting the return of Organisation Components
                     as specified in the Trading Role Information
                     Request Component.
 TradingRoleInfoReq  The Trading Role Information Request Component
                     (see section 7.4) contains a list of Trading
                     Roles about which information is being requested
 There must be at least one Component (either an Authentication
 Request or a Trading Role Information Request) within the
 Authentication Block otherwise it is an error.

8.5 Authentication Response Block

 The Authentication Response Block contains the response which results
 from processing the Authentication Request Block. Its definition is
 as follows.
 <!ELEMENT AuthRespBlk (AuthResp?, Org*) >
 <!ATTLIST AuthRespBlk
  ID                 ID      #REQUIRED >
 Attributes:
 ID                 An identifier which uniquely identifies the
                    Authentication Response Block within the IOTP
                    Transaction.
 Content:
 AuthResp           The optional Authentication Response Component
                    which contains the results of processing the
                    Authentication Request Component - see section
                    7.3.
 Org                Optional Organisation Components that contain
                    information corresponding to the Trading Roles as
                    requested by the TradingRoleList attribute of the
                    Trading Role Information Request component.

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 The components present in the Authentication Response Block must
 match the requirement of the corresponding Authentication Request
 Block otherwise it is an error.

8.6 Authentication Status Block

 The Authentication Status Block indicates the success or failure of
 the validation of an Authentication Response Block by an
 Authenticator. Its definition is as follows.
 <!ELEMENT AuthStatusBlk (Status) >
 <!ATTLIST AuthStatusBlk
  ID                 ID      #REQUIRED >
 Attributes:
 ID                 An identifier which uniquely identifies the
                    Authentication Status Block within the IOTP
                    Transaction.
 Content:
 Status             Contains status information about the business
                    success (see section 4.2) or failure of the
                    authentication

8.7 Payment Request Block

 The Payment Request Block contains information which requests that a
 payment is started. Its definition is as follows.
 <!ELEMENT PayReqBlk (Status+, BrandList, BrandSelection,
      Payment, PaySchemeData?, Org*, TradingRoleData*) >
 <!ATTLIST PayReqBlk
  ID                 ID      #REQUIRED >
 Attributes:
 ID                 An identifier which uniquely identifies the
                    Payment Request Block within the IOTP Transaction.
 Content:
 Status             Contains the Status Components (see section 7.13)
                    of the responses of the steps (e.g., an Offer
                    Response and/or a Payment Response) on which this

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                    step depends. It is used to indicate the success
                    or failure of those steps. Payment should only
                    occur if the previous steps were successful.
 BrandList          The Brand List Component contains a list of one or
                    more payment brands and protocols which may be
                    selected (see section 7.7).
 BrandSelection     This identifies the choice of payment brand, the
                    payment protocol and the Payment Handler to be
                    used in a payment within the IOTP Transaction.
                    There is one Brand Selection Component (see
                    section 7.8) for each payment to be made in the
                    IOTP Transaction.
 Payment            The Payment Components contain information about
                    the payment which is being made see section 7.9.
 PaySchemeData      The Payment Scheme Component contains payment
                    scheme specific data see section 7.10.
 Org                The Organisation Component contains details of
                    Organisations involved in the payment (see section
                    7.6). The Organisations present are dependent on
                    the IOTP Transaction and the data which is to be
                    signed. See section 6 Digital Signatures for more
                    details.
 TradingRoleData    The Trading Role Data Component contains opaque
                    data which is needs to be communicated between the
                    Trading Roles involved in an IOTP Transaction (see
                    section 7.17).
 The Payment Request Block should contain:
 o  the Organisation Component with a Trading Role of Merchant
 o  the Organisation Component with the Trading Role of Consumer
 o  the Payment Component for the Payment
 o  the Brand List Component for the Payment
 o  the Brand Selection Component for the Brand List
 o  the Organisation Component for the Payment Handler of the Payment

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 o  the Organisation Component (if any) for the Organisation which
    carried out the previous step, for example another Payment Handler
 o  the Organisation Component for the Organisation which is to carry
    out the next step, if any. This may be, for example, either a
    Delivery Handler or a Payment Handler.
 o  the Organisation Components for any additional Organisations that
    the Merchant has included in the Offer Response Block
 o  an Optional Payment Scheme Data Component, if required by the
    Payment Method as defined in the IOTP supplement for the payment
    method
 o  any Trading Role Data Components that may be required (see section
    7.17.1).

8.8 Payment Exchange Block

 The Payment Exchange Block contains payment scheme specific data
 which is exchanged between two of the roles in a trade. Its
 definition is as follows.
 <!ELEMENT PayExchBlk (PaySchemeData+) >
 <!ATTLIST PayExchBlk
  ID                 ID      #REQUIRED >
 Attributes:
 ID                 An identifier which uniquely identifies the
                    Payment Exchange Block within the IOTP
                    Transaction.
 Content:
 PaySchemeData      This Trading Component contains payment scheme
                    specific data see section 7.10 Payment Scheme
                    Component.

8.9 Payment Response Block

 This Payment Response Block contains a information about the Payment
 Status, an optional Payment Receipt, and an optional payment protocol
 message. Its definition is as follows.

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 <!ELEMENT PayRespBlk (Status, PayReceipt?, PaySchemeData?,
      PaymentNote?, TradingRoleData*) >
 <!ATTLIST PayRespBlk
  ID                 ID      #REQUIRED >
 Attributes:
 ID                 An identifier which uniquely identifies the
                    Payment Response Block within the IOTP
                    Transaction.
 Content:
 Status             Contains status information about the business
                    success (see section 4.2) or failure of the
                    payment. Note that in a Pay Response Block, a
                    ProcessState of NotYetStarted or InProgress are
                    illegal values.
 PayReceipt         Contains payment scheme specific data which can be
                    used to verify the payment occurred. See section
                    7.11 Payment Receipt Component. It must be present
                    if the ProcessState attribute of the Status
                    Component is set to CompletedOk. PayReceipt is
                    optional for other values as specified by the
                    appropriate Payment Scheme supplement.
 PaySchemeData      Contains payment scheme specific data see section,
                    for example a payment protocol message. See 7.10
                    Payment Scheme Component.
 PaymentNote        Contains additional, non payment related,
                    information which the Payment Handler wants to
                    provide to the Consumer. For example, if a
                    withdrawal or deposit were being made then it
                    could contain information on the remaining balance
                    on the account after the transfer was complete.
                    See section 7.12 Payment Note Component.
 TradingRoleData    The Trading Role Data Component contains opaque
                    data which is needs to be communicated between the
                    Trading Roles involved in an IOTP Transaction (see
                    section 7.17).

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8.10 Delivery Request Block

 The Delivery Request Block contains details of the goods or services
 which are to be delivered together with a signature which can be used
 to check that delivery is authorised. Its definition is as follows.
 <!ELEMENT DeliveryReqBlk (Status+, Order, Org*, Delivery,
      ConsumerDeliveryData?, TradingRoleData*) >
 <!ATTLIST DeliveryReqBlk
  ID                 ID      #REQUIRED >
 Attributes:
 ID                 An identifier which uniquely identifies the
                    Delivery Request Block within the IOTP
                    Transaction.
 Content:
 Status                Contains the Status Components (see section
                       7.13) of the responses of the steps (e.g., a
                       Payment Response) on which this step is
                       dependent. It is used to indicate the success
                       or failure of those steps. Delivery should only
                       occur if the previous steps were successful.
 Order                 The Order Component contains details about the
                       goods, services or financial transaction which
                       is taking place see section 7.5.
                       The Organisation Components (see section 7.6)
                       identify the Organisations and their roles in
 Org                   the IOTP Transaction. The roles and
                       Organisations which must be present will depend
                       on the particular type of IOTP Transaction. See
                       the definition of each transaction in section
                       9. Internet Open Trading Protocol Transactions.
 Delivery              The Delivery Component contains details of the
                       delivery to be made (see section 7.13).
 ConsumerDeliveryData  Optional. Contains an identifier specified by
                       the Consumer which, if returned by the Delivery
                       Handler will enable the Consumer to identify
                       which Delivery is being referred to.

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 TradingRoleData       The Trading Role Data Component contains opaque
                       data which is needs to be communicated between
                       the Trading Roles involved in an IOTP
                       Transaction (see section 7.17).
 The Delivery Request Block contains:
 o  the Organisation Component with a Trading Role of Merchant
 o  the Organisation Component for the Consumer and DeliverTo Trading
    Roles
 o  the Delivery Component for the Delivery
 o  the Organisation Component for the Delivery Handler. Specifically
    the Organisation Component identified by the ActionOrgRef
    attribute on the Delivery Component
 o  the Organisation Component (if any) for the Organisation which
    carried out the previous step, for example a Payment Handler
 o  the Organisation Components for any additional Organisations that
    the Merchant has included in the Offer Response Block
 o  any Trading Role Data Components that may be required (see section
    7.17.1).

8.11 Delivery Response Block

 The Delivery Response Block contains a Delivery Note containing
 details on how the goods will be delivered. Its definition is as
 follows. Note that in a Delivery Response Block a Delivery Status
 Element with a DeliveryStatusCode of NotYetStarted or InProgress is
 invalid.
 <!ELEMENT DeliveryRespBlk (Status, DeliveryNote) >
 <!ATTLIST DeliveryRespBlk
  ID                 ID      #REQUIRED >
 Attributes:
 ID                 An identifier which uniquely identifies the
                    Delivery Response Block within the IOTP
                    Transaction.
 Content:

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 Status             Contains status information about the business
                    success (see section 4.2) or failure of the
                    delivery.  Note that in a Delivery Response Block,
                    a ProcessState of NotYetStarted or InProgress are
                    illegal values.
 DeliveryNote       The Delivery Note Component contains details about
                    how the goods or services will be delivered (see
                    section 7.15).

8.12 Inquiry Request Trading Block

 The Inquiry Request Trading Block contains an Inquiry Type Component
 and an optional Payment Scheme Component to contain payment scheme
 specific inquiry messages.
 <!ELEMENT InquiryReqBlk ( InquiryType, PaySchemeData? ) >
 <!ATTLIST InquiryReqBlk
  ID                 ID      #REQUIRED >
 Attributes:
 ID                 An identifier which uniquely identifies the
                    Inquiry Request Trading Block within the IOTP
                    Transaction.
 Content:
 InquiryType        Inquiry Type Component (see section 7.18) that
                    contains the type of inquiry.
 PaySchemeData      Payment Scheme Component (see section 7.10) that
                    contains payment scheme specific inquiry messages
                    for inquiries on payments. This is present when
                    the Type attribute of Inquiry Type Component is
                    Payment.

8.13 Inquiry Response Trading Block

 The Inquiry Response Trading Block contains a Status Component and an
 optional Payment Scheme Component to contain payment scheme specific
 inquiry messages. Its purpose is to enquire on the current status of
 an IOTP transaction at a server.

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 <!ELEMENT InquiryRespBlk (Status, PaySchemeData?) >
 <!ATTLIST InquiryRespBlk
  ID                 ID      #REQUIRED
  LastReceivedIotpMsgRef NMTOKEN #IMPLIED
  LastSentIotpMsgRef  NMTOKEN #IMPLIED >
 Attributes:
 ID                      An identifier which uniquely identifies the
                         Inquiry Response Trading Block within the
                         IOTP Transaction.
 LastReceivedIotpMsgRef  Contains an Element Reference (see section
                         3.5) to the Message Id Component (see section
                         3.3.2) of the last message this server has
                         received from the Consumer. If there is no
                         previously received message from the Consumer
                         in the pertinent transaction, this attribute
                         should be contain the value Null. This
                         attribute exists for debugging purposes.
 LastSentIotpMsgRef      Contains an Element Reference (see section
                         3.5) to the Message Id Component (see section
                         3.3.2) of the last message this server has
                         sent to the Consumer. If there is no
                         previously sent message to the Consumer in
                         the pertinent transaction, this attribute
                         should contain the value Null. This attribute
                         exists for debugging purposes.
 Content:
 Status             Contains status information about the business
                    success (see section 4.2) or failure of a certain
                    trading exchange (i.e., Offer, Payment, or
                    Delivery).
 PaySchemeData      Payment Scheme Component (see section 7.10) that
                    contains payment scheme specific inquiry messages
                    for inquiries on payments. This is present when
                    the Type attribute of StatusType attribute of the
                    Status Component is set to Payment.

Burdett Informational [Page 178] RFC 2801 IOTP/1.0 April 2000

8.14 Ping Request Block

 The Ping Request Block is used to determine if a Server is operating
 and whether or not cryptography is compatible.
 The definition of a Ping Request Block is as follows.
 <!ELEMENT PingReqBlk (Org*)>
 <!ATTLIST PingReqBlk
  ID                 ID      #REQUIRED>
 Attributes:
 ID                 An identifier which uniquely identifies the Ping
                    Request Trading Block within the IOTP Transaction.
 Content:
 Org                Optional Organisation Components (see section
                    7.6).
                    If no Organisation Component is present then the
                    Ping Request is anonymous and simply determines if
                    the server is operating.
                    However if Organisation Components are present,
                    then it indicates that the sender of the Ping
                    Request wants to verify that digital signatures
                    can be handled.
                    In this case the sender includes:
                     o an Organisation Component that identifies
                       itself specifying the Trading Role(s) it is
                       taking in IOTP transactions (Merchant, Payment
                       Handler, etc.)
                     o an Organisation Component that identifies the
                       intended recipient of the message.
                    These are then used to generate a signature over
                    the Ping Response Block.

8.15 Ping Response Block

 The Ping Response Trading Block provides the result of a Ping
 Request.
 It contains an Organisation Component that identifies the sender of
 the Ping Response.

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 If the Ping Request to which this block is a response contained
 Organisation Components, then it also contains those Organisation
 Components.
 <!ELEMENT PingRespBlk (Org+)>
 <!ATTLIST PingRespBlk
  ID                 ID      #REQUIRED
  PingStatusCode (Ok | Busy | Down) #REQUIRED
  SigVerifyStatusCode (Ok | NotSupported | Fail) #IMPLIED
  xml:lang           NMTOKEN #IMPLIED
  PingStatusDesc     CDATA   #IMPLIED>
 Attributes:
 ID                   An identifier which uniquely identifies the Ping
                      Request Trading Block within the IOTP
                      Transaction.
 PingStatusCode       Contains a code which shows the status of the
                      sender software which processes IOTP messages.
                      Valid values are:
                       o Ok. Everything with the service is working
                        normally, including the signature
                        verification.
                       o Busy. Things are working normally but there
                        may be some delays.
                       o Down. The server is not functioning fully but
                        can still provide a Ping response.
 SigVerifyStatusCode  Contains a code which shows the status of
                      signature verification. This is present only
                      when the message containing the Ping Request
                      Block also contains a Signature Block. Valid
                      values are:
                       o Ok. The signature has successfully been
                        verified and proved compatible.
                       o NotSupported The receiver of this Ping
                        Request Block does not support validation of
                        signatures.
                       o Fail. Signature verification failed.
 Xml:lang             Defines the language used in PingStatusDesc.
                      This is present when PingStatusDesc is present.
 PingStatusDesc       Contains a short description of the status of
                      the server which sends this Ping Response Block.
                      Servers, if their designers want, can use this

Burdett Informational [Page 180] RFC 2801 IOTP/1.0 April 2000

                      attribute to send more refined status
                      information than PingStatusCode which can be
                      used for debugging purposes, for example.
 Content:
 Org                These are Organisation Components (see section
                    7.6).
                    The Organisation Components of the sender of the
                    Ping Response is always included in addition to
                    the Organisation Components sent in the Ping
                    Request.
 Note: Ping Status Code values do not include a value such as Fail,
 since, when the software receiving the Ping Request message is not
 working at all, no Ping Response message will be sent back.

8.16 Signature Block

 The Signature Block contains one or more Signature Components and
 associated Certificates (if required) which sign data associated with
 the IOTP Transaction. For a general discussion and introduction to
 how IOTP uses signatures, see section 6 Digital Signatures. The
 definition of the Signature Component and certificates is contained
 in the paper "Digital Signatures for the Internet Open Trading
 Protocol", see [IOTPDSIG].  Descriptions of how these are used by
 IOTP is contained in sections 7.19 and 7.20.
 The definition of a Signature Block is as follows:
 <!ELEMENT IotpSignatures (Signature+, Certificate*) >
 <!ATTLIST IotpSignatures
   ID                ID      #IMPLIED >
 Attributes:
 ID                 An identifier which uniquely identifies the
                    Signature Block within the IOTP Transaction.
 Content:
 Signature          A Signature Component. See section 7.19.
 Certificate        A Certificate Component. See section 7.20.

Burdett Informational [Page 181] RFC 2801 IOTP/1.0 April 2000

 The contents of a Signature Block depends on the Trading Block that
 is contained in the same IOTP Message as the Signature Block.

8.16.1 Signature Block with Offer Response

 A Signature Block which is in the same message as an Offer Response
 Block contains just an Offer Response Signature Component (see
 section 7.19.2).

8.16.2 Signature Block with Payment Request

 A Signature Block which is in the same message as a Payment Request
 Block contains:
 o  an Offer Response Signature Component (see section 7.19.2), and
 o  if the Payment is dependent on an earlier step (as indicated by
    the StartAfter attribute on the Payment Component), then the
    Payment Receipt Signature Component (see section 7.19.3) generated
    by the previous step

8.16.3 Signature Block with Payment Response

    A Signature Block which is in the same message as a Payment
    Response Block contains just a Payment Receipt Signature Component
    (see section 7.19.3) generated by the step.

8.16.4 Signature Block with Delivery Request

    A Signature Block which is in the same message as a Delivery
    Request Block contains:
 o  an Offer Response Signature Component (see section 7.19.2), and
 o  the Payment Receipt Signature Component (see section 7.19.3)
    generated by the previous step.

8.16.5 Signature Block with Delivery Response

 A Signature Block which is in the same message as a Delivery Response
 Block contains just a Delivery Response Signature component (see
 section 7.19.4) generated by the step.

Burdett Informational [Page 182] RFC 2801 IOTP/1.0 April 2000

8.17 Error Block

 The Error Trading Block contains one or more Error Components (see
 section 7.21) which contain information about Technical Errors (see
 section 4.1) in an IOTP Message which has been received by one of the
 Trading Roles involved in the trade.
 For clarity two phrases are defined which are used in the description
 of an Error Trading Block:
 o  message in error. An IOTP message which contains or causes an
    error of some kind
 o  message reporting the error. An IOTP message that contains an
    Error Trading Block that describes the error found in a message in
    error.
 An Error Trading Block may be contained in any message reporting the
 error. The action which then follows depends on the severity of the
 error. See the definition of an Error Component, for an explanation
 of the different types of severity and the actions which can then
 occur.
 in3 Note: Although, an Error Trading Block can report multiple
 different errors using multiple Error Components, there is no
 obligation on a developer of an IOTP Aware Application to do so.
 The structure of an Error Trading Block is as follows.
 <!ELEMENT ErrorBlk (ErrorComp+, PaySchemeData*) >
 <!ATTLIST ErrorBlk
  ID                 ID      #REQUIRED >
 Attributes:
 ID                 An identifier which uniquely identifies the Error
                    Trading Block within the IOTP Transaction.
 Content:
 ErrorComp          An Error Components (see section 7.21) that
                    contains information about an individual Technical
                    Error.
 PaySchemeData      An optional Payment Scheme Component (see section
                    7.10) which contains a Payment Scheme Message. See
                    the appropriate payment scheme supplement to

Burdett Informational [Page 183] RFC 2801 IOTP/1.0 April 2000

                    determine whether or not this component needs to
                    be present and for the definition of what it must
                    contain.

8.18 Cancel Block

 The Cancel Block is used by one Trading Role to inform any other that
 a transaction has been cancelled. Example usage includes:
 o  a Consumer Role informing a non-Consumer role that it no longer
    plans to continue with the transaction. This will allow the server
    to close down the transaction tidily without a waiting for a
    time-out to occur
 o  a non-Consumer Role to inform a Consumer role that the Transaction
    is being stopped. In this case, the Consumer is then unlikely to
    re-send the previous message that was sent in the mistaken
    understanding that the original was not received.
 Its definition is as follows.
 <!ELEMENT CancelBlk (Status) >
 <!ATTLIST CancelBlk
  ID                 ID      #REQUIRED >
 Attributes:
 ID                 An identifier which uniquely identifies the Cancel
                    Block within the IOTP Transaction.
 Content:
 Status             Contains status information indicating that the
                    IOTP transaction has been cancelled.

9. Internet Open Trading Protocol Transactions

 The Baseline Internet Open Trading Protocol supports three types of
 transactions for different purposes. These are
 o  an Authentication IOTP transaction which supports authentication
    of one party in a trade by another and/or requests information
    about another Trading Role

Burdett Informational [Page 184] RFC 2801 IOTP/1.0 April 2000

 o  IOTP Transactions that involve one or more payments. Specifically:
  1. Deposit
  1. Purchase
  1. Refund
  1. Withdrawal, and
  1. Value Exchange
 o  IOTP Transactions designed to check the correct function of the
    IOTP infrastructure. Specifically:
  1. Transaction Status Inquiry, and
  1. Ping
 Although the Authentication IOTP Transaction can operate on its own,
 authentication can optionally precede any of the "payment"
 transactions.  Therefore, the rest of this section is divided into
 two parts covering:
 o  Authentication and Payment transactions (Authentication, Deposit,
    Purchase, Refund, Withdrawal and Value Exchange)
 o  Infrastructure Transactions (Transaction Status Inquiry and Ping)
    that are designed to support inquiries on whether or not a
    transaction has succeeded or a Trading Role's servers are
    operating correctly, and

9.1 Authentication and Payment Related IOTP Transactions

    The Authentication and Payment related IOTP Transactions consist
    of six Document Exchanges which are then combined in sequence to
    implement a specific transaction.
    Generally, there is a close, but not exact, correspondence between
    a Document Exchange and a Trading Exchange. The main difference is
    that some Document Exchanges implement part or all of two Trading
    Exchanges simultaneously in order to minimise the number of actual
    IOTP Messages which must be sent over the Internet.
    The six Document Exchanges are:
 o  Authentication. This is a direct implementation of the
    Authentication Trading Exchange

Burdett Informational [Page 185] RFC 2801 IOTP/1.0 April 2000

 o  Brand Dependent Offer. This is the Offer Trading Exchange combined
    with the Brand Selection part of the Payment Trading Exchange. Its
    purpose is to provide the Merchant with information on the Brand
    selected so that the content of the Offer Response may be adapted
    accordingly
 o  Brand Independent Offer. This is also an Offer Trading Exchange.
    However, in this instance, the content of the Offer Response does
    not depend on the Brand selected.
 o  Payment. This is a direct implementation of the Payment part of a
    Payment Trading Exchange
 o  Delivery. This is a direct implementation of the Delivery Exchange
 o  Delivery with Payment. This is an implementation of combined
    Payment and Delivery Trading Exchanges
 These Document Exchanges are combined together in different sequences
 to implement each IOTP Transaction. The way in which they may be
 combined is illustrated by the diagram below.

Burdett Informational [Page 186] RFC 2801 IOTP/1.0 April 2000

  • +*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*
   START -----------------------------------------------------
    |                                                         v
    |                                                ----------------
    |                                               | AUTHENTICATION |
    |                                                ----------------
     --------------------------------------               |    |
                     |                     |              |    |
                     |      -------------- | -------------     |
                     v      v              v      v            |
                -------------------     -----------------      |
               | BRAND INDEPENDENT |   | BRAND DEPENDENT |     |
               |       OFFER       |   |      OFFER      |     |
                -------------------     -----------------      |
                      |    |                   |   |           |
                      |     ---------------    |   |           |
                      |                    |   |   |           |
                      |     -------------- | --    |           |
                      v    v               v       v           |
                    ---------           --------------         |
                   | PAYMENT |         | PAYMENT WITH |        |
                   | (first) |         |   DELIVERY   |        |
                    ---------           --------------         |
                        |                      |               |
            -----------------------------      |               |
            v                v           |     |               |
       ----------        ---------       |     |               |
      | DELIVERY |      | PAYMENT |      |     |               |
      |          |      | {second)|      |     |               |
       ----------        ---------       |     |               |
            |                |           |     |               v
             ----------------------------------------------> STOP
  • -*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*
       Figure 17 Payment and Authentication Message Flow Combinations
 The combinations of Document Exchanges that are valid depend on the
 particular IOTP transaction.
 The remainder of this sub-section describes:
 o  each Document Exchange in more detail including descriptions of
    the content of each Trading Block in the Document Exchanges, and
 o  descriptions of how each IOTP Transaction uses the Document
    Exchanges to effect the desired result.

Burdett Informational [Page 187] RFC 2801 IOTP/1.0 April 2000

 Note: The descriptions of the Document Exchanges which follow
 describe the ways in which various Business Errors (see section 4.2)
 are handled. No reference is made however to the handling of
 Technical Errors (see section 4.1) in any of the messages since these
 are handled the same way irrespective of the context in which the
 message is being sent. See section 4 for more details.

9.1.1 Authentication Document Exchange

 The Authentication Document Exchange is a direct implementation of
 the Authentication Trading Exchange (see section 2.2.4). It involves:
 o  an Authenticator - the Organisation which is requesting the
    authentication, and
 o  an Authenticatee - the Organisation being authenticated.
 The authentication consists of:
 o  an Authentication Request being sent by the Authenticator to the
    Authenticatee,
 o  an Authentication Response being sent in return by the
    Authenticatee to the Authenticator which is then checked, and
 o  an Authentication Status being sent by the Authenticator to the
    Authenticatee to provide an indication of the success or failure
    of the authentication.
 An Authentication Document Exchange also:
 o  provides an Authenticatee with an Organisation Component which
    describes the Authenticator, and
 o  optionally provides the Authenticator with Organisation Components
    which describe the Authenticatee.
 The Authentication Request may also be digitally signed which allows
 the Authenticatee to verify the credentials of the Authenticator.
 The IOTP Messages which are involved are illustrated by the diagram
 below.

Burdett Informational [Page 188] RFC 2801 IOTP/1.0 April 2000

*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+* Organisation 1 (Authenticatee)

   |   Organisation 2
   |  (Authenticator)

STEP | | 1. First Organisation takes an action (for example by

           pressing a button on an HTML page) which requires that
           the Organisation is authenticated
   1 --> 2 Authentication Need (outside scope of IOTP)

2. The second Organisation generates: an Authentication

           Request Block containing one or more Authentication
           Request Components and/or a Trading Role Information
           Request Component, then sends it to the first
           Organisation
   1 <-- 2 TPO & AUTHENTICATION REQUEST. IotpMsg: Trans Ref Block;
           Signature Block (optional); TPO Block; Auth Request Block

3. IOTP aware application started. If a Signature Block is

           present, the first Organisation may use this to check the
           credentials of the second Organisation. If credentials are
           OK, the first Organisation selects an Authentication
           Request to use (if present and more than one), then uses
           the authentication algorithm selected to generate an
           Authentication Response Block. If present, the Trading
           Role Information Request Component is used to generate
           Organisation Components. Finally a Signature Component is
           created if required and all components are then sent back
           to the second Organisation for validation.
   1 --> 2 AUTHENTICATION RESPONSE. IotpMsg; Trans Ref Block;
           Signature Block (optional) ; Auth Response Block

4. The second Organisation checks the Authentication

           Response against the data in the Authentication Request
           Block to check that the first Organisation is who they
           appear to be, and sends an Authentication Status Block to
           the first Organisation to indicate the result then
           stops.
   1 <-- 2 AUTHENTICATION STATUS. IotpMsg: Trans Ref Block;
           Signature Block (optional); Auth Response Block

Burdett Informational [Page 189] RFC 2801 IOTP/1.0 April 2000

5. The first Organisation checks the authentication Status

           Block and optionally keeps information on the IOTP
           transaction for record keeping purposes and stops.

*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*

               Figure 18 Authentication Document Exchange

9.1.1.1 Message Processing Guidelines

 On receiving a TPO & Authentication Request IOTP Message (see below),
 an Authenticatee may either:
 o  generate and send an Authentication Response IOTP Message back to
    the Authenticator, or
 o  indicate failure to comply with the Authentication Request by
    sending a Cancel Block back to the Authenticator containing a
    Status Component with a StatusType of Authentication a
    ProcessState of Failed and the CompletionCode (see section 7.16.4)
    set to either: AutEeCancel, NoAuthReq, TradRolesIncon or
    Unspecified.
 On receiving an Authentication Response IOTP Message (see below), an
 Authenticator should send in return, an Authentication Status IOTP
 Message (see below) containing a Status Block with a Status Component
 where the StatusType is set to Authentication, and:
 o  the ProcessState attribute of the Status Component is set to
    CompletedOk which indicates a successful completion, or
 o  the ProcessState attribute is set to Failed and the CompletionCode
    attribute is set to either: AutOrCancel, AuthFailed or Unspecified
    which indicates a failed authentication,
 On receiving an Authentication Status IOTP Message (see below), the
 Authenticatee should check the Status Component in the Status Block.
 If this indicates:
 o  a successful authentication, then the Authenticatee should either:
  1. continue with the next step in the IOTP Transaction of which

the Authentication Document Exchange is part (if any), or

Burdett Informational [Page 190] RFC 2801 IOTP/1.0 April 2000

  1. indicate a failure to continue with the rest of the IOTP

Transaction, by sending back to the Authenticator a Cancel

       Block containing a Status Component with a StatusType of
       Authentication, a ProcessState of Failed and the CompletionCode
       (see section 7.16.4) set to AutEeCancel.
 o  a failed authentication, then the failure should be reported to
    the Authenticatee and any further processing stopped.
 If the Authenticator receives an IOTP Message containing a Cancel
 block from a Consumer, then the Authenticatee may go to the
 CancelNetLocn specified on the Trading Role Element in the
 Organisation Component for the Authenticator contained in the Trading
 Protocol Options Block.

9.1.1.2 TPO & Authentication Request IOTP Message

 Apart from a Transaction Reference Block (see section 3.3), this
 message consists of:
 o a Trading Protocol Options Block (see section 8.1)
 o an Authentication Request Block (see section 8.4), and
 o an optional Signature Block (see section 8.16).
 Each of these are described below.
 TRADING PROTOCOL OPTIONS BLOCK
 The Trading Protocol Options Block (see section 8.1) must contain the
 following Trading Components:
 o  one Protocol Options Component (see Section 7.1) which defines the
    options which apply to the whole Authentication Document Exchange.
 o  one Organisation Component (see section 7.6) which describes the
    Authenticator. The Trading Role on the Organisation Component
    should indicate the role which the Authenticator is taking in the
    Trade, for example a Merchant or a Consumer.
 AUTHENTICATION REQUEST BLOCK
 The Authentication Request Block (see section 8.4) must contain the
 following Trading Components:
 o  one Authentication Request Component (see section 7.2), and

Burdett Informational [Page 191] RFC 2801 IOTP/1.0 April 2000

 SIGNATURE BLOCK (AUTHENTICATION REQUEST)
 If the Authentication Request is being digitally signed then a
 Signature Block must be included. It contains Digests of the
 following XML elements:
 o  the Transaction Reference Block (see section 3.3) for the IOTP
    Message that contains information that describes the IOTP Message
    and IOTP Transaction
 o  the Transaction Id Component (see section 3.3.1) which globally
    uniquely identifies the IOTP Transaction
 o  the following components of the TPO Block :
  1. the Protocol Options Component
  1. the Organisation Component
 o  the following components of the Authentication Request Block:
  1. the Authentication Request Component
  1. the Trading Role Information Request Component

9.1.1.3 Authentication Response IOTP Message

 Apart from a Transaction Reference Block (see section 3.3), this
 message consists of:
 o  an Authentication Response Block (see section 8.5), and
 o  an optional Signature Block (see section 8.16).
 Each of these are described below.
 AUTHENTICATION RESPONSE BLOCK
 The Authentication Response Block must contain the following Trading
 Component:
 o  one Authentication Response Component (see section 7.3)
 o  one Organisation Component for every Trading Role identified in
    the TradingRoleList attribute of the Trading Role Information
    Request Component contained in the Authentication Request Block.

Burdett Informational [Page 192] RFC 2801 IOTP/1.0 April 2000

 SIGNATURE BLOCK (AUTHENTICATION RESPONSE)
 If the Algorithm element (see section 12. IANA Considerations) within
 the Authentication Request Component contained in the Authentication
 Request Block indicates that the Authentication Response should
 consist of a digital signature then a Signature Block must be
 included in the same IOTP message that contains an Authentication
 Response Block. The Signature Component contains Digest Elements for
 the following XML elements:
 o  the Transaction Reference Block (see section 3.3) for the IOTP
    Message that contains information that describes the IOTP Message
    and IOTP Transaction
 o  the Transaction Id Component (see section 3.3.1) which globally
    uniquely identifies the IOTP Transaction
 o  the following components of the Authentication Request Block:
  1. the Authentication Request Component
  1. the Trading Role Information Request Component
 o  the Organisation Components contained in the Authentication
    Response Block
 Note: It should not be assumed that all trading roles can support the
 signing of data. Particularly it should not be assumed that Consumers
 support the signing of data.

9.1.1.4 Authentication Status IOTP Message

 Apart from a Transaction Reference Block (see section 3.3), this
 message consists of:
 o  an Authentication Status Block (see section 8.5), and
 o  an optional Signature Block (see section 8.16).
 Each of these are described below.
 AUTHENTICATION STATUS BLOCK
 The Authentication Status Block (see section 8.6) must contain the
 following Trading Components:
 o  one Status Component (see section 7.16) with a ProcessState
    attribute set to CompletedOk.

Burdett Informational [Page 193] RFC 2801 IOTP/1.0 April 2000

    SIGNATURE BLOCK (AUTHENTICATION STATUS)
    If the Authentication Status Block is being digitally signed then
    a Signature Block must be included that contains a Signature
    Component with Digest elements for the following XML elements:
 o  the Transaction Reference Block (see section 3.3) for the IOTP
    Message that contains information that describes the IOTP Message
    and IOTP Transaction
 o  the Transaction Id Component (see section 3.3.1) which globally
    uniquely identifies the IOTP Transaction
 o  the following components of the Authentication Status Block:
  1. the Status Component (see section 7.16).
 Note: If the Authentication Document Exchange is followed by an Offer
 Document Exchange (see section 9.1.2) then the Authentication Status
 Block and the Signature Block (Authentication Status) may be combined
 with either:
 o a TPO IOTP Message (see section 9.1.2.3), or
 o a TPO and Offer Response IOTP Message (see section 9.1.2.6)

9.1.2 Offer Document Exchange

 The Offer Document Exchange occurs in two basic forms:
 o  Brand Dependent Offer Exchange. Where the content of the offer,
    e.g., the order details, amount, delivery details, etc., are
    dependent on the payment brand and protocol selected by the
    consumer, and
 o  Brand Independent Offer Exchange. Where the content of the offer
    is not dependent on the payment brand and protocol selected.
    Each of these types of Offer Document Exchange may be preceded by
    an Authentication Document Exchange (see section 9.1.1).

9.1.2.1 Brand Dependent Offer Document Exchange

    In a Brand Dependent Offer Document Exchange the TPO Block and the
    Offer Response Block are sent separately by the Merchant to the
    Consumer, i.e.:

Burdett Informational [Page 194] RFC 2801 IOTP/1.0 April 2000

 o  the Brand List Component is sent to the Consumer in a TPO Block,
 o  the Consumer selects a Payment Brand, Payment Protocol and
    optionally a Currency and amount from the Brand List Component
 o  the Consumer sends the selected brand, protocol and
    currency/amount back to the Merchant in a TPO Selection Block, and
 o  the Merchant uses the information received to define the content
    of and then send the Offer Response Block to the Consumer.

Burdett Informational [Page 195] RFC 2801 IOTP/1.0 April 2000

This is illustrated by the diagram below.

*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*

 Consumer
   |  Merchant

STEP | | 1. Consumer decides to trade and sends to the Merchant

           information (e.g., using HTML) that enables the Merchant
           to create an offer,
   C --> M Offer information - outside scope of IOTP

2. Merchant decides which payment brand protocols,

           currencies and amounts apply, places then in a Brand List
           Component inside a TPO Block and sends to Consumer
   C <-- M TPO. IotpMsg: Trans Ref Block; TPO Block

3. IOTP aware application started. Consumer selects the

           payment brand, payment protocol and currency/amount to
           use. Records selection in a Brand Selection Component and
           sends back to Merchant.
   C --> M TPO SELECTION. IotpMsg: Trans Ref Block; TPO Selection
           Block

4. Merchant uses selected payment brand, payment protocol,

           currency/amount and the offer information to create an
           Offer Response Block containing details about the IOTP
           Transaction including price, etc. Optionally signs it and
           sends to the Consumer
   C <-- M OFFER RESPONSE. IotpMsg: Trans Ref Block; Signature Block
           (optional); Offer Response Block

5. Consumer checks the Offer is OK, then combines components

           from the TPO Block, the TPO Selection Block and the Offer
           Response Block to create the next IOTP Message for the
           Transaction and sends it together with the Signature
           block if present to the required Trading Role
   CONTINUED ...

*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*

            Figure 19 Brand Dependent Offer Document Exchange

Burdett Informational [Page 196] RFC 2801 IOTP/1.0 April 2000

 Note, a Consumer identifies a Brand Dependent Offer Document
 Exchange, by the absence of an Offer Response Block in the first IOTP
 Message.
 MESSAGE PROCESSING GUIDELINES
 On receiving a TPO IOTP Message (see below), the Consumer may either:
 o  generate and send a TPO Selection IOTP Message back to the
    Merchant, or
 o  indicate failure to continue with the IOTP Transaction by sending
    a Cancel Block back to the Merchant containing a Status Component
    with a StatusType of Offer, a ProcessState of Failed and the
    CompletionCode (see section 7.16.4) set to either: ConsCancelled
    or Unspecified.
 On receiving a TPO Selection IOTP Message (see below) the Merchant
 may either:
 o  generate and send an Offer Response IOTP Message back to the
    Consumer, or
 o  indicate failure to continue with the IOTP Transaction by sending
    a Cancel Block back to the Consumer containing a Status Component
    with a StatusType of Offer, a ProcessState of Failed and the
    CompletionCode (see section 7.16.4) set to either: MerchCancelled
    or Unspecified.
 On receiving an Offer Response IOTP Message (see below) the Consumer
 may either:
 o  generate and send the next IOTP Message in the IOTP transaction
    and send it to the required Trading Role. This is dependent on the
    IOTP Transaction, or
 o  indicate failure to continue with the IOTP Transaction by sending
    a Cancel Block back to the Merchant containing a Status Component
    with a StatusType of Offer, a ProcessState of Failed and the
    CompletionCode (see section 7.16.4) set to either: ConsCancelled
    or Unspecified.
 If the Merchant receives an IOTP Message containing a Cancel block,
 then the Consumer is likely to go to the CancelNetLocn specified on
 the Trading Role Element in the Organisation Component for the
 Merchant.

Burdett Informational [Page 197] RFC 2801 IOTP/1.0 April 2000

 If the Consumer receives an IOTP Message containing a Cancel block,
 then the information contained in the IOTP Message should be reported
 to the Consumer but no further action taken.

9.1.2.2 Brand Independent Offer Document Exchange

 In a Brand Independent Offer Document Exchange the TPO Block and the
 Offer Response Block are sent together by the Merchant to the
 Consumer, i.e. there is one IOTP Message that contains both a TPO
 Block, and an Offer Response Block.
 The message flow is illustrated by the diagram below:

*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+* Consumer

   |  Merchant

STEP | | 1. Consumer decides to trade and sends to the Merchant

           information (e.g., using HTML) that enables the Merchant
           to create an offer,
   C --> M Offer information - outside scope of IOTP

2. Merchant decides which payment brand protocols,

           currencies and amounts apply, places then in a Brand List
           Component inside a TPO Block, creates an Offer Response
           containing details about the IOTP Transaction including
           price, etc., optionally signs it  and sends to Consumer
   C <-- M TPO & OFFER RESPONSE. IotpMsg: Trans Ref Block; Signature
           Block; TPO Block; Offer Response Block

3. IOTP aware application started. Consumer selects the

           payment brand, payment protocol and currency/amount to
           use. Records selection in a Brand Selection Component,
           checks offer is OK, combines the Brand Selection
           Component with information from the TPO Block and Offer
           Response Block to create the next IOTP Message for the
           Transaction and sends it together with the Signature
           Block if present to the required Trading Role.
   CONTINUED ...

*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*

               Figure 20 Brand Independent Offer Exchange

Burdett Informational [Page 198] RFC 2801 IOTP/1.0 April 2000

 Note that a Brand Independent Offer Document Exchange always occurs
 when only one payment brand, protocol and currency/amount is being
 offered to the Consumer by the Merchant. It is also likely to, but
 will not necessarily, occur when multiple brands are being offered,
 the Payment Handler is the same, and all brands use the same set of
 protocols.
 Note that the TPO Block and the Offer Response Block can be sent in
 separate IOTP messages (see Brand Dependent Offer Document Exchange)
 even if the Offer Response Block does not change. However this
 increases the number of messages in the transaction and is therefore
 likely to increase transaction response times.
 IOTP aware applications supporting the Consumer Trading Role must
 check for the existence of an Offer Response Block in the first IOTP
 Message to determine whether the Offer Document Exchange is brand
 dependent or not.
 MESSAGE PROCESSING GUIDELINES
 On receiving a TPO and Offer Response IOTP Message (see below), the
 Consumer may either:
 o  generate and send the next IOTP Message in the IOTP transaction
    and send it to the required Trading Role. This is dependent on the
    IOTP Transaction, or
 o  indicate failure to continue with the IOTP Transaction by sending
    a Cancel Block back to the Merchant containing a Status Component
    with a StatusType of Offer, a ProcessState of Failed and the
    CompletionCode (see section 7.16.1) set to either: ConsCancelled
    or Unspecified.
 If the Merchant receives an IOTP Message containing a Cancel block,
 then the Consumer is likely to go to the CancelNetLocn specified on
 the Trading Role Element in the Organisation Component for the
 Merchant.

9.1.2.3 TPO IOTP Message

 The TPO IOTP Message is only used with a Brand Dependent Offer
 Document Exchange. Apart from a Transaction Reference Block (see
 section 3.3), this message consists of just a Trading Protocol
 Options Block (see section 8.1) which is described below.

Burdett Informational [Page 199] RFC 2801 IOTP/1.0 April 2000

 TPO (TRADING PROTOCOL OPTIONS) BLOCK
 The Trading Protocol Options Block (see section 8.1) must contain the
 following Trading Components:
 o  one Protocol Options Component which defines the options which
    apply to the whole IOTP Transaction. See Section 7.1.
 o  one Brand List Component (see section 7.7) for each Payment in the
    IOTP Transaction that contain one or more payment brands and
    protocols which may be selected for use in each payment
 o  Organisation Components (see section 7.6) with the following
    roles:
  1. Merchant who is making the offer
  1. Consumer who is carrying out the transaction
  1. the PaymentHandler(s) for the payment. The "ID" of the Payment

Handler Organisation Component is contained within the PhOrgRef

       attribute of the Payment Component
 If the IOTP Transaction includes a Delivery then the TPO Block must
 also contain:
 o  Organisation Components with the following roles:
  1. DeliveryHandler who will be delivering the goods or services
  1. DelivTo i.e. the person or Organisation which is to take

delivery

 AUTHENTICATION STATUS AND SIGNATURE BLOCKS
 If the Offer Document Exchange was preceded by an Authentication
 Document Exchange, then the TPO IOTP Message may also contain:
 o  an Authentication Status Block (see section 8.6), and
 o  an optional Signature Block (Authentication Status) Signature
    Block
 See section 9.1.1.4 Authentication Status IOTP Message for more
 details.

Burdett Informational [Page 200] RFC 2801 IOTP/1.0 April 2000

9.1.2.4 TPO Selection IOTP Message

 The TPO Selection IOTP Message is only used with a Brand Dependent
 Offer Document Exchange. Apart from a Transaction Reference Block
 (see section 3.3), this message consists of just a TPO Selection
 Block (see section 8.1) which is described below.
 TPO SELECTION BLOCK
 The TPO Selection Block (see section 8.2) contains:
 o  one Brand Selection Component (see section 7.8) for use in a
    later Payment Exchange. It contains the results of the consumer
    selecting a Payment Brand, Payment Protocol and currency/amount
    from the list provided in the Brand List Component.

9.1.2.5 Offer Response IOTP Message

 The Offer Response IOTP Message is only used with a Brand Dependent
 Offer Document Exchange. Apart from a Transaction Reference Block
 (see section 3.3), this message consists of:
 o  an Offer Response Block (see section 8.1) and
 o  an optional Signature Block (see section 8.16).
 OFFER RESPONSE BLOCK
 The Offer Response Block (see section 8.3) contains the following
 components:
 o  one Status Component (see section 7.16) which indicates the status
    of the Offer Response. The ProcessState attribute should be set to
    CompletedOk
 o  one Order Component (see section 7.5) which contains details about
    the goods and services which are being purchased or the financial
    transaction which is taking place
 o  one or more Payment Component(s) (see section 7.9) for each
    payment which is to be made
 o  zero or one Delivery Components (see section 7.13) containing
    details of the delivery to be made if the IOTP Transaction
    includes a delivery
 o  zero or more Trading Role Data Components (see section 7.17) if
    required by the Merchant.

Burdett Informational [Page 201] RFC 2801 IOTP/1.0 April 2000

 SIGNATURE BLOCK (OFFER RESPONSE)
 If the Authentication Status Block is being digitally signed then a
 Signature Block must be included that contains a Signature Component
 (see section 7.19) with Digest Elements for the following XML
 elements:
 If the Offer Response is being digitally signed then a Signature
 Block must be included that contains a Signature Component (see
 section 7.19) with Digest Elements for the following XML elements:
 o  the Transaction Reference Block (see section 3.3) for the IOTP
    Message that contains information that describes the IOTP Message
    and IOTP Transaction
 o  the Transaction Id Component (see section 3.3.1) which globally
    uniquely identifies the IOTP Transaction
 o  the following components of the TPO Block :
  1. the Protocol Options Component, and
  1. the Brand List Component
  1. all the Organisation Components present
 o  the following components of the Offer Response Block:
  1. the Order Component
  1. all the Payment Components present
  1. the Delivery Component if present
  1. any Trading Role Data Components present

9.1.2.6 TPO and Offer Response IOTP Message

 The TPO and Offer Response IOTP Message is only used with a Brand
 Independent Offer Document Exchange. Apart from a Transaction
 Reference Block (see section 3.3), this message consists of:
 o  a Trading Protocol Options Block (see section 8.1)
 o  an Offer Response Block (see section 8.1) and
 o  an optional Signature Block (see section 8.16).

Burdett Informational [Page 202] RFC 2801 IOTP/1.0 April 2000

 TPO (TRADING PROTOCOL OPTIONS) BLOCK
 This is the same as the Trading Protocol Options Block described in
 TPO IOTP Message (see section 9.1.2.3).
 OFFER RESPONSE BLOCK
 This the same as the Offer Response Block in the Offer Response IOTP
 Message (see section 9.1.2.5).
 AUTHENTICATION STATUS
 If the Offer Document Exchange was preceded by an Authentication
 Document Exchange, then the TPO and Offer Response IOTP Message may
 also contain an Authentication Status Block (see section 8.6).
 SIGNATURE BLOCK
 This is the same as the Signature Block in the Offer Response IOTP
 Message (see section 9.1.2.5) with the addition that:
 o  if the Offer Document Exchange is Brand Dependent then the
    Signature Component in the Signature Block additionally contains a
    Digest Element for the Brand Selection Component contained in the
    TPO Selection Block
 o  if the Offer Document Exchange was preceded by an Authentication
    Document Exchange then the Signature Component in the Signature
    Block additionally contains a Digest Element for the
    Authentication Status Block.

9.1.3 Payment Document Exchange

 The Payment Document Exchange is a direct implementation of the last
 part of a Payment Trading Exchange (see section 2.2.2) after the
 Brand has been selected by the Consumer. A Payment Exchange consists
 of:
 o  the Consumer requesting that a payment starts by generating
    Payment Request IOTP Message using information from previous IOTP
    Messages in the Transaction and then sending it to the Payment
    Handler
 o  the Payment Handler and the Consumer then swapping Payment
    Exchange IOTP Messages encapsulating payment protocol messages
    until the payment is complete, and finally

Burdett Informational [Page 203] RFC 2801 IOTP/1.0 April 2000

 o  the Payment Handler sending a Payment Response IOTP Message to the
    Consumer containing a receipt for the payment.
 The IOTP Messages which are involved are illustrated by the diagram
 below.

*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*

 Consumer
   |  Payment
   |  Handler

STEP | | 1. Consumer generates Pay Request Block encapsulating a

           payment protocol message if required and sends to Payment
           Handler with the Signature Block if present
   C --> P PAYMENT REQUEST. IotpMsg: Trans Ref Block; Signature
           Block (optional); Pay Request Block

2. Payment Handler processes Pay Request Block, checks

           optional signature and starts exchanging payment protocol
           messages encapsulated in a Pay Exchange Block, with the
           Consumer
   C <-> P PAYMENT EXCHANGE. IotpMsg: Trans Ref Block; Pay Exchange
           Block

3. Consumer and Payment Handler keep on exchanging Payment

           Exchange blocks until eventually payment protocol
           messages finish so Payment Handler creates a Pay Receipt
           Component inside a Pay Response Block, and an optional
           Signature Component inside a Signature Block, sends them
           to the Consumer and stops.
   C <-- P PAYMENT RESPONSE. IotpMsg: Trans Ref Block; Signature
           Block (optional); Pay Response Block

4. Consumer checks Payment Response is OK. Optionally keeps

           information on IOTP Transaction for record keeping
           purposes and either stops or creates the next IOTP
           message for the Transaction and sends it together with
           the Signature Block, if present, to the required Trading
           Role

*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*

                   Figure 21 Payment Document Exchange

Burdett Informational [Page 204] RFC 2801 IOTP/1.0 April 2000

9.1.3.1 Message Processing Guidelines

 On receiving a Payment Request IOTP Message, the Payment Handler
 should check that they are authorised to carry out the Payment (see
 section 6 Digital Signatures). They may then either:
 o  generate and send a Payment Exchange IOTP Message back to the
    Consumer, if more payment protocol messages need to be exchanged,
    or
 o  generate and send a Payment Response IOTP Message if the exchange
    of payment protocol messages is complete, or
 o  indicate failure to continue with the Payment by sending a Cancel
    Block back to the Consumer containing a Status Component with a
    StatusType of Payment, a ProcessState of Failed and the
    CompletionCode (see section 7.16.4) set to either: BrandNotSupp,
    CurrNotSupp, PaymtCancelled, AuthError, InsuffFunds,
    InstBrandInvalid, InstNotValid, BadInstrument or Unspecified.
 On receiving a Payment Exchange IOTP Message, the Consumer may
 either:
 o  generate and send a Payment Exchange Message back to the Payment
    Handler or
 o  indicate failure to continue with the Payment by sending a Cancel
    Block back to the Payment Handler containing a Status Component
    with a StatusType of Payment, a ProcessState of Failed and the
    CompletionCode (see section 7.16.2) set to either: ConsCancelled
    or Unspecified.
 On receiving a Payment Exchange IOTP Message, the Payment Handler may
 either:
 o  generate and send a Payment Exchange IOTP Message back to the
    Consumer, if more payment protocol messages need to be exchanged,
    or
 o  generate and send a Payment Response IOTP Message if the exchange
    of payment protocol messages is complete, or
 o  indicate failure to continue with the Payment by sending a Cancel
    Block back to the Consumer containing a Status Component with a
    StatusType of Payment, a ProcessState of Failed and the
    CompletionCode (see section 7.16.2) set to either: PaymtCancelled
    or Unspecified.

Burdett Informational [Page 205] RFC 2801 IOTP/1.0 April 2000

 On receiving a Payment Response IOTP Message, the Consumer may
    either:
 o  generate and send the next IOTP Message in the IOTP transaction
    and send it to the required Trading Role. This is dependent on the
    IOTP Transaction,
 o  stop, since the IOTP Transaction has ended, or
 o  indicate failure to continue with the IOTP Transaction by sending
    a Cancel Block back to the Merchant containing a Status Component
    with a StatusType of Payment, a ProcessState of Failed and the
    CompletionCode (see section 7.16.1) set to either: ConsCancelled
    or Unspecified.
 If the Consumer receives an IOTP Message containing a Cancel block,
 then the information contained in the IOTP Message should be reported
 to the Consumer but no further action taken.
 If the Payment Handler receives an IOTP Message containing a Cancel
 block, then the Consumer is likely to go to the CancelNetLocn
 specified on the Trading Role Element in the Organisation Component
 for the Payment Handler from which any further action may take place.
 If the Merchant receives an IOTP Message containing a Cancel block,
 then the Consumer should have completed the payment but not
 continuing with the transaction for some reason. In this case the
 Consumer is likely to go to the CancelNetLocn specified on the
 Trading Role Element in the Organisation Component for the Merchant
 from which any further action may take place.

9.1.3.2 Payment Request IOTP Message

 Apart from a Transaction Reference Block (see section 3.3), this
 message consists of:
 o  a Payment Request Block, and
 o  an optional Signature Block
 PAYMENT REQUEST BLOCK
 The Payment Request Block (see section 8.7) contains:
 o  the following components copied from the Offer Response Block from
    the preceding Offer Document Exchange:
  1. the Status Component

Burdett Informational [Page 206] RFC 2801 IOTP/1.0 April 2000

  1. the Payment Component for the payment which is being carried

out

 o  the following components from the TPO Block:
  1. the Organisation Components with the roles of Merchant and for

the PaymentHandler that is being sent the Payment Request Block

  1. the Brand List Component for the payment, i.e. the Brand List

referred to by the BrandListRef attribute on the Payment

       Component
 o  one Brand Selection Component for the Brand List, i.e. the Brand
    Selection Component where BrandListRef attribute points to the
    Brand List. This component can be either:
  1. copied from the TPO Selection Block if the payment was preceded

by a Brand Dependent Offer Document Exchange (see section

       9.1.2.1), or
  1. created by the Consumer, containing the payment brand, payment

protocol and currency/amount selected from the Brand List, if

       the payment was preceded by a Brand Independent Offer Document
       Exchange (see section 9.1.2.2)
 o  an optional Payment Scheme Component (see section 7.10) if
    required by the payment method used (see the Payment Method
    supplement to determine if this is needed).
 o  zero or more Trading Role Data Components (see section 7.17).
 Note that:
 o  if there is more than one Payment Components in an Offer Response
    Block, then the second payment is the one within the Offer
    Response Block that contains a StartAfter attribute (see section
    7.9) that identifies the Payment Component for the first payment
 o  the Payment Handler to include is identified by the Brand
    Selection Component (see section 7.8) for the payment. Also see
    section 6.3.1 Check Request Block sent Correct Organisation for an
    explanation on how Payment Handlers are identified
 o  the Brand List Component to include is the one identified by the
    BrandListRef attribute of the Payment Component for the identified
    payment

Burdett Informational [Page 207] RFC 2801 IOTP/1.0 April 2000

 o  the Brand Selection Component to include from the Offer Response
    Block is the one that contains an BrandListRef attribute (see
    section 3.5) which identifies the Brand List Component for the
    second payment.
 SIGNATURE BLOCK (PAYMENT REQUEST)
 If the either the preceding Offer Document Exchange included an Offer
 Response Signature (see section 9.1.2.5 Offer Response IOTP Message),
 or a preceding Payment Exchange included a Payment Response Signature
 (see section 9.1.3.4 Payment Response IOTP Message) then they should
 both be copied to the Signature Block in the Payment Request IOTP
 Message.

9.1.3.3 Payment Exchange IOTP Message

 Apart from a Transaction Reference Block (see section 3.3), this
 message consists of just a Payment Exchange Block.
 PAYMENT EXCHANGE BLOCK
 The Payment Exchange Block (see section 8.8) contains:
 o  one Payment Scheme Component (see section 7.10) which contains
    payment method specific data. See the Payment Method supplement
    for the payment method being used to determine what this should
    contain.

9.1.3.4 Payment Response IOTP Message

 Apart from a Transaction Reference Block (see section 3.3), this
 message consists of:
 o  a Payment Response Block, and
 o  an optional Signature Block
 PAYMENT RESPONSE BLOCK
 The Payment Response Block (see section 8.9) contains:
 o  one Payment Receipt Component (see section 7.11) which contains
    scheme specific data which can be used to verify the payment
    occurred

Burdett Informational [Page 208] RFC 2801 IOTP/1.0 April 2000

 o  one Payment Scheme Component (see section 7.10) if required which
    contains payment method specific data. See the Payment Method
    supplement for the payment method being used to determine what
    this should contain
 o  an optional Payment Note Component (see section 7.12)
 o  zero or more Trading Role Data Components (see section 7.17).
 SIGNATURE BLOCK (PAYMENT RESPONSE)
 If a signed Payment Receipt is being provided, indicated by the
 SignedPayReceipt attribute of the Payment Component being set to
 True, then the Signature Block should contain a Signature Component
 which contains Digest Elements for the following:
 o  the Transaction Reference Block (see section 3.3) for the IOTP
    Message which contains the first usage of the Payment Response
    Block,
 o  the Transaction Id Component (see section 3.3.1) within the
    Transaction Reference Block that globally uniquely identifies the
    IOTP Transaction,
 o  the Payment Receipt Component from the Payment Response Block,
 o  the Payment Note Component from the Payment Response Block,
 o  the other Components referenced by the PayReceiptNameRefs
    attribute (if present) of the Payment Receipt Component,
 o  the Status Component from the Payment Response Block,
 o  any Trading Role Data Components in the Payment Response Block,
    and
 o  all the Signature Components contained in the Payment Request
    Block if present.

9.1.4 Delivery Document Exchange

 The Delivery Document Exchange is a direct implementation of a
 Delivery Trading Exchange (see section 2.2.3). It consists of:
 o  the Consumer requesting a Delivery by generating Delivery Request
    IOTP Message using information from previous IOTP Messages in the
    Transaction and then sending it to the Delivery Handler

Burdett Informational [Page 209] RFC 2801 IOTP/1.0 April 2000

 o  the Delivery Handler sending a Delivery Response IOTP Message to
    the Consumer containing details about the Handler's response to
    the request together with an optional signature.
 The message flow is illustrated by the diagram below.

*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+* Consumer

   |  Delivery
   |  Handler

STEP | | 1. Consumer generates Delivery Request Block and sends it to

           the Delivery Handler with the Signature Block if present
   C --> D DELIVERY REQUEST. IotpMsg: Trans Ref Block; Signature
           Block; Delivery Request Block

2. Delivery Handler checks the Status and Order Components

           in the Delivery Request and the optional Signatures,
           creates a Delivery Response Block, sends to the Consumer
           and stops.
   C <-- D DELIVERY RESPONSE. IotpMsg: Trans Ref Block; Signature
           Block; Delivery Response Block

3. Consumer checks Delivery Response Block and optional

           Signature Block are OK. Optionally keeps information on
           IOTP Transaction for record keeping purposes and stops.

*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*

                  Figure 22 Delivery Document Exchange

9.1.4.1 Message Processing Guidelines

 On receiving a Delivery Request IOTP Message, the Delivery Handler
 should check that they are authorised to carry out the Delivery (see
 section 6 Digital Signatures). They may then either:
 o  generate and send a Delivery Response IOTP Message to the
    Consumer, or
 o  indicate failure to continue with the Delivery by sending a Cancel
    Block back to the Consumer containing a Status Component with a
    StatusType of Delivery, a ProcessState of Failed and the
    CompletionCode (see section 7.16.4) set to either: DelivCanceled,
    or Unspecified.

Burdett Informational [Page 210] RFC 2801 IOTP/1.0 April 2000

 On receiving a Delivery Response IOTP Message, the Consumer should
 just stop since the IOTP Transaction is complete.
 If the Consumer receives an IOTP Message containing a Cancel block,
 then the information contained in the IOTP Message should be reported
 to the Consumer but no further action taken.

9.1.4.2 Delivery Request IOTP Message

 The Delivery Request IOTP Message consists of:
 o  a Delivery Request Block, and
 o  an optional Signature Block
 DELIVERY REQUEST BLOCK
 The Delivery Request Block (see section 8.10) contains:
 o  the following components copied from the Offer Response Block:
  1. the Status Component (see section 7.16)
  1. the Order Component (see section 7.5)
  1. the Organisation Component (see section 7.6) with the roles of:

Merchant, DeliveryHandler and DeliverTo

  1. the Delivery Component (see section 7.13)
 o  the following Component from the Payment Response Block:
  1. the Status Component (see section 7.16).
 o  zero or more Trading Role Data Components (see section 7.17).
 SIGNATURE BLOCK (DELIVERY REQUEST)
 If the preceding Offer Document Exchange included an Offer Response
 Signature or the Payment Document Exchange included a Payment
 Response Signature, then they should both be copied to the Signature
 Block.

9.1.4.3 Delivery Response IOTP Message

 The Delivery Response IOTP Message contains a Delivery Response Block
 and an optional Signature Block.

Burdett Informational [Page 211] RFC 2801 IOTP/1.0 April 2000

 DELIVERY RESPONSE BLOCK
 The Delivery Response Block contains:
 o  one Delivery Note Component (see section 7.15) which contains
    delivery instructions about the delivery of goods or services
    in3 SIGNATURE BLOCK (DELIVERY RESPONSE)
    The Signature Block should contain one Signature Component that
    contains Digest elements that refer to
 o  the Transaction Id Component (see section 3.3.1) of the IOTP
    message that contains the Delivery  Response Signature
 o  the Transaction Reference Block (see section 3.3) of the IOTP
    Message that contains the Delivery  Response Signature
 o  the Consumer Delivery Data component contained in the Delivery
    Request Block (if any)
 o  the Signature Components contained in the Delivery Request Block
    (if any)
 o  the Status Component
 o  the Delivery Note Component

9.1.5 Payment and Delivery Document Exchange

 The Payment and Delivery Document Exchange is a combination of the
 last part of the Payment Trading Exchange (see section 2.2.2) and a
 Delivery Trading Exchange (see section 2.2.3). It consists of:
 o  the Consumer requesting that a payment starts by generating
    Payment Request IOTP Message using information from previous IOTP
    Messages in the Transaction and then sending it to the Payment
    Handler
 o  the Payment Handler and the Consumer then swapping Payment
    Exchange IOTP Messages encapsulating payment protocol messages
    until the payment is complete, and finally
 o  the Payment Handler sending to the Consumer in one IOTP Message:
  1. a Payment Response Block containing a receipt for the payment,

and

Burdett Informational [Page 212] RFC 2801 IOTP/1.0 April 2000

  1. a Delivery Response Block containing details of the goods or

services to be delivered

 The IOTP Messages which are involved are illustrated by the diagram
 below.

Burdett Informational [Page 213] RFC 2801 IOTP/1.0 April 2000

*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+* Consumer

   |  Payment
   |  Handler

STEP | | 1. Consumer generates Pay Request Block encapsulating a

           payment protocol message if required and sends to Payment
           Handler with the Signature Block if present
   C --> P PAYMENT REQUEST. IotpMsg: Trans Ref Block; Signature
           Block; Pay Request Block

2. Payment Handler processes Pay Request Block, checks

           optional signature and starts exchanging payment protocol
           messages encapsulated in a Pay Exchange Block, with the
           Consumer
   C <-> P PAYMENT EXCHANGE. IotpMsg: Trans Ref Block; Pay Exchange
           Block

3. Consumer and Payment Handler keep on exchanging Payment

           Exchange blocks until eventually payment protocol
           messages finish so Payment Handler creates a Pay Receipt
           Component inside a Pay Response Block, and an optional
           Signature Component inside a Signature Block, then uses
           information from the Offer Response Bock to create a
           Delivery Response Block and sends both to the Consumer
           and stops.
   C <-- P PAYMENT RESPONSE & DELIVERY RESPONSE. IotpMsg: Trans Ref
           Block; Signature Block; Pay Response Block; Delivery
           Response Block

4. Consumer checks Payment Response and Delivery Response

           Blocks are OK. Optionally keeps information on IOTP
           Transaction for record keeping purposes and either stops
           or creates the next IOTP message for the Transaction and
           sends it together with the Signature Block, if present,
           to the required Trading Role

*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*

            Figure 23 Payment and Delivery Document Exchange

Burdett Informational [Page 214] RFC 2801 IOTP/1.0 April 2000

 The Delivery Response Block and the Payment Response Block may be
 combined into the same IOTP Message only if the Payment Handler has
 the information available so that she can send the Delivery Response
 Block.  This is likely to, but will not necessarily, occur when the
 Merchant, the Payment Handler and the Delivery Handler Roles are
 combined.
 The DelivAndPayResp attribute of the Delivery Component (see section
 7.13) contained within the Offer Response Block (see section 8.3) is
 set to True if the Delivery Response Block and the Payment Response
 Block are combined into the same IOTP Message and is set to False if
 the Delivery Response Block and the Payment Response Block are sent
 in separate IOTP Messages.

9.1.5.1 Message Processing Guidelines

 On receiving a Payment Request IOTP Message or a Payment Exchange
 IOTP Message, the Payment Handler should carry out the same actions
 as for a Payment Document Exchange (see section 9.1.3.1).
 On receiving a Payment Exchange IOTP Message, the Consumer should
 also carry out the same actions as for a Payment Document Exchange
 (see section 9.1.3.1).
 On receiving a Payment Response and Delivery Response IOTP Message
 then the IOTP Transaction is complete and should take no further
 action.
 If the Consumer receives an IOTP Message containing a Cancel block,
 then the information contained in the IOTP Message should be reported
 to the Consumer but no further action taken.
 If the Payment Handler receives an IOTP Message containing a Cancel
 block, then the Consumer is likely to go to the CancelNetLocn
 specified on the Trading Role Element in the Organisation Component
 for the Payment Handler from which any further action may take place.
 If the Merchant receives an IOTP Message containing a Cancel block,
 then the Consumer should have completed the payment but not
 continuing with the transaction for some reason. In this case the
 Consumer is likely to go to the CancelNetLocn specified on the
 Trading Role Element in the Organisation Component for the Merchant
 from which any further action may take place.

9.1.5.2 Payment Request IOTP Message

 The content of this message is the same as for a Payment Request IOTP
 Message in a Payment Document Exchange (see section 9.1.3.2).

Burdett Informational [Page 215] RFC 2801 IOTP/1.0 April 2000

9.1.5.3 Payment Exchange IOTP Message

 The content of this message is the same as for a Payment Exchange
 IOTP Message in a Payment Document Exchange (see section 9.1.3.3).

9.1.5.4 Payment Response and Delivery Response IOTP Message

 The content of this message consists of:
 o  a Payment Response Block,
 o  an optional Signature Block (Payment Response), and
 o  a Delivery Response Block.
 PAYMENT RESPONSE BLOCK
 The content of this block is the same as the Payment Response Block
 in the Payment Response IOTP Message associated with a Payment
 Document Exchange (see section 9.1.3.4).
 SIGNATURE BLOCK (PAYMENT RESPONSE)
 The content of this block is the same as the Signature Block (Payment
 Response) in the Payment Response IOTP Message associated with a
 Payment Document Exchange (see section 9.1.3.4).
 DELIVERY RESPONSE BLOCK
 The content of this block is the same as the Delivery Response Block
 in the Delivery Response IOTP Message associated with a Delivery
 Document Exchange (see section 9.1.4.3).

9.1.6 Baseline Authentication IOTP Transaction

 A Baseline Authentication IOTP Transaction may occur at any time
 between any of the Trading Roles involved in IOTP Transactions. This
 means it could occur:
 o  before another IOTP Transaction
 o  at the same time as another IOTP Transaction
 o  independently of any other IOTP Transaction.
 The Baseline Authentication IOTP Transaction consists of just an
 Authentication Document Exchange (see section 9.1.1) as illustrated
 by the diagram below.

Burdett Informational [Page 216] RFC 2801 IOTP/1.0 April 2000

  • +*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*
 START -------------------------------------------------------
                                                              v
                                                     ----------------
                                                    | AUTHENTICATION |
                                                     ----------------
                                                               |
                                                               |
                                                               |
                                                               |
                -------------------     -----------------      |
               | BRAND INDEPENDENT |   | BRAND DEPENDENT |     |
               |       OFFER       |   |      OFFER      |     |
                -------------------     -----------------      |
                                                               |
                                                               |
                                                               |
                                                               |
                                                               |
                    ---------           --------------         |
                   | PAYMENT |         | PAYMENT WITH |        |
                   | (first) |         |   DELIVERY   |        |
                    ---------           --------------         |
                                                               |
                                                               |
                                                               |
       ----------        ---------                             |
      | DELIVERY |      | PAYMENT |                            |
      |          |      | {second)|                            |
       ----------        ---------                             |
                                                               v
                                                             STOP
  • -*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*
             Figure 24 Baseline Authentication IOTP Transaction
 Example uses of the Baseline Authentication IOTP Transaction include:
 o  when the Baseline Authentication IOTP Transaction takes place as
    an early part of a session where strong continuity exists. For
    example, a Financial Institution could:
  1. set up a secure channel (e.g., using [SSL/TLS]) with a customer
  1. authenticate the customer using the Baseline Authentication

IOTP Transaction, and then

Burdett Informational [Page 217] RFC 2801 IOTP/1.0 April 2000

  1. provide the customer with access to account information and

other services with the confidence that they are communicating

       with a bona fide customer.
 o  as a means of providing a Merchant role with Organisation
    Components that contain information about Consumer and DelivTo
    Trading Roles
 o  so that a Consumer may authenticate a Payment Handler before
    starting a payment.

9.1.7 Baseline Deposit IOTP Transaction

 The Baseline Deposit IOTP Transaction supports the deposit of
 electronic cash with a Financial Institution.
 Note: The Financial Institution has, in IOTP terminology, a role of
 merchant in that a service (i.e. a deposit of electronic cash) is
 being offered in return for a fee, for example bank charges of some
 kind. The term "Financial Institution" is used in the diagrams and in
 the text for clarity.
 The Baseline Deposit IOTP Transaction consists of the following
 Document Exchanges:
 o  an optional Authentication Document Exchange (see section 9.1.1)
 o  an Offer Document Exchange (see section 9.1.2), and
 o  a Payment Document Exchange (see section 9.1.3).
 The way in which these Document Exchanges may be combined together is
 illustrated by the diagram below.

Burdett Informational [Page 218] RFC 2801 IOTP/1.0 April 2000

  • +*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*
 START -----------------------------------------------------
    |                                                       v
    |                                                ----------------
    |                                               | AUTHENTICATION |
    |                                                ----------------
     --------------------------------------               |
                     |                     |              |
                     |      -------------- | -------------
                     v      v              v      v
                -------------------     -----------------
               | BRAND INDEPENDENT |   | BRAND DEPENDENT |
               |       OFFER       |   |      OFFER      |
                -------------------     -----------------
                      |                        |
                      |                        |
                      |                        |
                      |     -------------------
                      v    v
                    ---------           --------------
                   | PAYMENT |         | PAYMENT WITH |
                   | (first) |         |   DELIVERY   |
                    ---------           --------------
                        |
                         ----------------
                                         |
       ----------        ---------       |
      | DELIVERY |      | PAYMENT |      |
      |          |      | {second)|      |
       ----------        ---------       |
                                         |
                                          -----------------> STOP
  • -*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*
                 Figure 25 Baseline Deposit IOTP Transaction
 See section 9.1.12 "Valid Combinations of Document Exchanges" to
 determine which combination of document exchanges apply to a
 particular instance of an IOTP Transaction
 Note that:
 o  a Merchant (Financial Institution) may be able to accept a deposit
    in several different types of electronic cash although, since the
    Consumer role that is depositing the electronic cash usually knows
    what type of cash they want to deposit, it is usually constrained

Burdett Informational [Page 219] RFC 2801 IOTP/1.0 April 2000

    in practice to only one type. However, there may be several
    different protocols which may be used for the same "brand" of
    electronic cash. In this case a Brand Dependent Offer may be
    appropriate to negotiate the protocol to be used.
 o  the Merchant (Financial Institution) may use the results of the
    authentication to identify not only the consumer but also the
    account to which the payment is to be deposited. If no single
    account can be identified, then it must be obtained by other
    means. For example:
  1. the consumer could specify the account number prior to the

Baseline Deposit IOTP Transaction starting, or

  1. the consumer could have been identified earlier, for example

using a Baseline Authentication IOTP Transaction, and an

       account selected from a list provided by the Financial
       Institution.
 o  The Baseline Deposit IOTP Transaction without an Authentication
    Document Exchange might be used:
  1. if a previous IOTP transaction, for example a Baseline

Withdrawal or a Baseline Authentication, authenticated the

       consumer, and a secure channel has been maintained, therefore
       the authenticity of the consumer is known
  1. if authentication is achieved as part of a proprietary payment

protocol and is therefore included in the Payment Document

       Exchange
  1. if authentication of the consumer has been achieved by some

other means outside of the scope of IOTP, for example, by using

       a pass phrase, or a proprietary banking software solution.

9.1.8 Baseline Purchase IOTP Transaction

 The Baseline Purchase IOTP Transaction supports the purchase of goods
 or services using any payment method. It consists of the following
 Document Exchanges:
 o  an optional Authentication Document Exchange (see section 9.1.1)
 o  an Offer Document Exchange (see section 9.1.2)
 o  either:
  1. a Payment Document Exchange (see section 9.1.3) followed by

Burdett Informational [Page 220] RFC 2801 IOTP/1.0 April 2000

  1. a Delivery Document Exchange (see section 9.1.4)
 o  a Payment Document Exchange only, or
 o  a combined Payment and Delivery Document Exchange (see section
    9.1.5).
 The ways in which these Document Exchanges are combined is
 illustrated by the diagram below.
  • +*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*
 START -----------------------------------------------------
    |                                                       v
    |                                                ----------------
    |                                               | AUTHENTICATION |
    |                                                ----------------
     --------------------------------------               |    |
                     |                     |              |    |
                     |      -------------- | -------------     |
                     v      v              v      v            |
                -------------------     -----------------      |
               | BRAND INDEPENDENT |   | BRAND DEPENDENT |     |
               |       OFFER       |   |      OFFER      |     |
                -------------------     -----------------      |
                      |    |                   |   |           |
                      |     ---------------    |   |           |
                      |                    |   |   |           |
                      |     -------------- | --    |           |
                      v    v               v       v           |
                    ---------           --------------         |
                   | PAYMENT |         | PAYMENT WITH |        |
                   | (first) |         |   DELIVERY   |        |
                    ---------           --------------         |
                        |                      |               |
            -----------------------------      |               |
            v                            |     |               |
       ----------        ---------       |     |               |
      | DELIVERY |      | PAYMENT |      |     |               |
      |          |      | {second)|      |     |               |
       ----------        ---------       |     |               |
            |                            |     |               v
             ----------------------------------------------> STOP
  • -*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*
                Figure 26 Baseline Purchase IOTP Transaction

Burdett Informational [Page 221] RFC 2801 IOTP/1.0 April 2000

 See section 9.1.12 "Valid Combinations of Document Exchanges" to
 determine which combination of document exchanges apply to a
 particular instance of an IOTP Transaction.

9.1.9 Baseline Refund IOTP Transaction

 In business terms the refund process typically consists of:
 o  a request for a refund being made by the Consumer to the Merchant,
    typically supported by evidence to demonstrate:
  1. the original trade took place, for example by providing a

receipt for the original transaction

  1. using some type of authentication, that the consumer requesting

the refund is the consumer, or a representative of the

       consumer, who carried out the original trade
  1. the reason why the merchant should make the refund
 o  the merchant agreeing (or not) to the refund. This may involve
    some negotiation between the Consumer and the Merchant, and, if
    the merchant agrees,
 o  a refund payment by the Merchant to the Consumer.
 The Baseline Refund IOTP Transaction supports a subset of the above,
 specifically it supports:
 o  stand alone authentication of the Consumer using a separate
    Baseline Authentication IOTP Transaction (see section 9.1.6)
 o  a refund payment by the Merchant to the Consumer using the
    following two Trading Exchanges:
  1. an optional Authentication Document Exchange (see section

9.1.1)

  1. an Offer Document Exchange (see section 9.1.2), and
  1. a Payment Document Exchange (see section 9.1.3).
 The ways in which these Document Exchanges are combined is
 illustrated by the diagram below.

Burdett Informational [Page 222] RFC 2801 IOTP/1.0 April 2000

  • +*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*
 START -----------------------------------------------------
    |                                                       v
    |                                                ----------------
    |                                               | AUTHENTICATION |
    |                                                ----------------
     --------------------------------------               |
                     |                     |              |
                     |      -------------- | -------------
                     v      v              v      v
                -------------------     -----------------
               | BRAND INDEPENDENT |   | BRAND DEPENDENT |
               |       OFFER       |   |      OFFER      |
                -------------------     -----------------
                      |                        |
                      |                        |
                      |                        |
                      |     -------------------
                      v    v
                    ---------           --------------
                   | PAYMENT |         | PAYMENT WITH |
                   | (first) |         |   DELIVERY   |
                    ---------           --------------
                        |
                         ----------------
                                         |
       ----------        ---------       |
      | DELIVERY |      | PAYMENT |      |
      |          |      | {second)|      |
       ----------        ---------       |
                                         |
                                          -----------------> STOP
  • -*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*
                 Figure 27 Baseline Refund IOTP Transaction
 A Baseline Refund IOTP Transaction without an Authentication Document
 Exchange might be used:
 o  when authentication of the consumer has been achieved by some
    other means, for example, the consumer has entered some previously
    supplied code in order to identify herself and the refund to which
    the code applies. The code could be supplied, for example on a web
    page or by e-mail.

Burdett Informational [Page 223] RFC 2801 IOTP/1.0 April 2000

 o  when a previous IOTP transaction, for example a Baseline
    Authentication, authenticated the consumer, and a secure channel
    has been maintained, therefore the authenticity of the consumer is
    known and therefore the previously agreed refund can be
    identified.
 o  when the authentication of the consumer is carried out by the
    Payment Handler using a payment scheme authentication algorithm.

9.1.10 Baseline Withdrawal IOTP Transaction

 The Baseline Withdrawal IOTP Transaction supports the withdrawal of
 electronic cash from a Financial Institution.
 Note: The Financial Institution has, in IOTP terminology, a role of
 merchant in that a service (i.e. a withdrawal of electronic cash) is
 being offered in return for a fee, for example bank charges of some
 kind. The term "Financial Institution" is used in the diagrams and in
 the text for clarity.
 The Baseline Withdrawal IOTP Transaction consists of the following
 Document Exchanges:
 o  an optional Authentication Document Exchange (see section 9.1.1)
 o  an Offer Document Exchange (see section 9.1.2), and
 o  a Payment Document Exchange (see section 9.1.3).
 The way in which these Document Exchanges may be combined together is
 illustrated by the diagram below.

Burdett Informational [Page 224] RFC 2801 IOTP/1.0 April 2000

  • +*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*
 START -----------------------------------------------------
    |                                                       v
    |                                                ----------------
    |                                               | AUTHENTICATION |
    |                                                ----------------
     --------------------------------------               |
                     |                     |              |
                     |      -------------- | -------------
                     v      v              v      v
                -------------------     -----------------
               | BRAND INDEPENDENT |   | BRAND DEPENDENT |
               |       OFFER       |   |      OFFER      |
                -------------------     -----------------
                      |                        |
                      |                        |
                      |                        |
                      |     -------------------
                      v    v
                    ---------           --------------
                   | PAYMENT |         | PAYMENT WITH |
                   | (first) |         |   DELIVERY   |
                    ---------           --------------
                        |
                         ----------------
                                         |
       ----------        ---------       |
      | DELIVERY |      | PAYMENT |      |
      |          |      | {second)|      |
       ----------        ---------       |
                                         |
                                          -----------------> STOP
  • -*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*
               Figure 28 Baseline Withdrawal IOTP Transaction
 Note that:
 o  a Merchant (Financial Institution) may be able to offer withdrawal
    of several different types of electronic cash. In practice usually
    only one form of electronic cash may be offered. However, there
    may be several different protocols which may be used for the same
    "brand" of electronic cash.

Burdett Informational [Page 225] RFC 2801 IOTP/1.0 April 2000

 o  the Merchant (Financial Institution) may use the results of the
    authentication to identify not only the consumer but also the
    account from which the withdrawal is to be made. If no single
    account can be identified, then it must be obtained by other
    means. For example:
  1. the consumer could specify the account number prior to the

Baseline Withdrawal IOTP Transaction starting, or

  1. the consumer could have been identified earlier, for example

using a Baseline Authentication IOTP Transaction, and an

       account selected from a list provided by the Financial
       Institution.
 o  a Baseline Withdrawal without an authentication might be used:
  1. if a previous IOTP transaction, for example a Baseline Deposit

or a Baseline Authentication, authenticated the consumer, and a

       secure channel has been maintained, therefore the authenticity
       of the consumer is known
  1. if authentication is achieved as part of a proprietary payment

protocol and is therefore included in the Payment Document

       Exchange
  1. if authentication of the consumer has been achieved by some

other means, for example, by using a pass phrase, or a

       proprietary banking software solution.

9.1.11 Baseline Value Exchange IOTP Transaction

 The Baseline Value Exchange Transaction uses Payment Document
 Exchanges to support the exchange of value in one currency obtained
 using one payment method with value in the same or another currency
 using the same or another payment method. Examples of its use
 include:
 o  electronic cash advance on a credit card. For example the first
    payment could be a "dollar SET Payment" using a credit card with
    the second payment being a download of Visa Cash e-cash in
    dollars.
 o  foreign exchange using the same payment method. For example the
    payment could be an upload of Mondex value in British Pounds and
    the second a download of Mondex value in Euros

Burdett Informational [Page 226] RFC 2801 IOTP/1.0 April 2000

 o  foreign exchange using different payment methods. For example the
    first payment could be a SET payment in Canadian Dollars followed
    a download of GeldKarte in Deutchmarks.
 The Baseline Value Exchange uses the following Document Exchanges:
 o  an optional Authentication Document Exchange (see section 9.1.1)
 o  an Offer Document Exchange (see section 9.1.2), which provides
    details of what values and currencies will be exchanged, and
 o  two Payment Document Exchanges (see section 9.1.3) which carry out
    the two payments involved.
 The way in which these Document Exchanges may be combined together is
 illustrated by the diagram below.

Burdett Informational [Page 227] RFC 2801 IOTP/1.0 April 2000

  • +*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*
 START -----------------------------------------------------
    |                                                         v
    |                                                ----------------
    |                                               | AUTHENTICATION |
    |                                                ----------------
     --------------------------------------               |
                     |                     |              |
                     |      -------------- | -------------
                     v      v              v      v
                -------------------     -----------------
               | BRAND INDEPENDENT |   | BRAND DEPENDENT |
               |       OFFER       |   |      OFFER      |
                -------------------     -----------------
                      |                        |
                      |                        |
                      |                        |
                      |     -------------------
                      v    v
                    ---------           --------------
                   | PAYMENT |         | PAYMENT WITH |
                   | (first) |         |   DELIVERY   |
                    ---------           --------------
                        |
                         ----
                             v
       ----------        ---------
      | DELIVERY |      | PAYMENT |
      |          |      | {second)|
       ----------        ---------
                             |
                              -----------------------------> STOP
  • -*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*
             Figure 29 Baseline Value Exchange IOTP Transaction

Burdett Informational [Page 228] RFC 2801 IOTP/1.0 April 2000

 The Baseline Value Exchange IOTP Transaction occurs in two basic
 forms:
 o  Brand Dependent Value Exchange. Where the content of the offer,
    for example the rate at which one form of value is exchanged for
    another, is dependent on the payment brands and protocols selected
    by the consumer, and
 o  Brand Independent Value Exchange. Where the content of the offer
    is not dependent on the payment brands and protocols selected.
 Note: In the above the role is a Merchant even though the
 Organisation carrying out the Value Exchange may be a Bank or some
 other Financial Institution. This is because the Bank is acting as a
 merchant in that they are making an offer which the Consumer can
 either accept or decline.
 The TPO Block and Offer Response Block may only be combined into the
 same IOTP Message if the content of the Offer Response Block does not
 change as a result of selecting the payment brands and payment
 protocols to be used in the Value Exchange.
 BASELINE VALUE EXCHANGE SIGNATURES
 The use of signatures to ensure the integrity of a Baseline Value
 Exchange is illustrated by the diagram below.

Burdett Informational [Page 229] RFC 2801 IOTP/1.0 April 2000

*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*

Signature generated IotpMsg (TPO) by Merchant ensures - Trans Ref Block integrity of the Offer ——–> - - Signature Block

                               |   - TPO Block              MERCHANT
                               |   - Offer Response Block
                               |

Signature generated by | the Payment Handler of | IotpMsg (Pay Resp 1) the first payment binds | - Trans Ref Block PAYMENT Pay Receipt for the first —–> → - Signature Block —– HANDLER payment to the Offer - Pay Response Block 1 | 1

                                                          |

Signature generated by | the Payment Handler of IotpMsg (Pay Resp 2) | PAYMENT the second payment binds - Trans Ref Block | HANDLER the second payment to the —–> - Signature Block ←—– 2 first payment and therefore - Pay Response Block 2 to the Offer

*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*

            Figure 30 Baseline Value Exchange Signatures

9.1.12 Valid Combinations of Document Exchanges

 The following diagram illustrates the data conditions in the various
 IOTP messages which can be used by a Consumer Trading Role to
 determine whether the combination of Document Exchanges are valid.
  • +*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*
 START
   |
   v
 Auth Request Block in  =TRUE
  first IOTP Message ? ---------------------------------------
    | = FALSE                                                 |
    v                                                         v
 Offer Response Block in                             ----------------
   first IOTP Message ?                             | AUTHENTICATION |
    |=TRUE         |=FALSE                           ----------------
    |              |                                        |
    |              |                                        v

Burdett Informational [Page 230] RFC 2801 IOTP/1.0 April 2000

    |                ----------------------       TPO & Offer Response
     -------------                         |   Blocks in last IOTP Msg
                  |                        |     |=TRUE        |=FALSE
                  |                        |     |             v
                  |          ------------- | ----    TPO Block only if
                  |         |              |         last IOTP Message
                  |         |              |         of Authentication
                  |         |              |          |=TRUE   |=FALSE
                  v         v              v          v        |
                -------------------     -----------------      |
               | BRAND INDEPENDENT |   | BRAND DEPENDENT |     |
               |       OFFER       |   |      OFFER      |     |
                -------------------     -----------------      |
                        |                   |                  |
                        v                   v                  |
                     Offer Response Block contains             |
                           Delivery Component ?                |
                          |=FALSE        |=TRUE                |
                       ---               v                     |
                      |        Value of DelivAndPayResp        |
                      |    attribute of Delivery Component ?   |
                      |    |=FALSE         |=TRUE              |
                      |    |               |                   |
                      v    v               v                   |
                    ---------           --------------         |
                   | PAYMENT |         | PAYMENT WITH |        |
                   | (first) |         |   DELIVERY   |        |
                    ---------           --------------         |
                        |                      |               |
                        v                      |               |
          Offer and Response Block contains     -------------->|
                Delivery Component ?                           |
                |=TRUE           |=FALSE                       |
                |                v                             |
                |         Two Payment Components               |
                |      present in Offer Response Block?        |
                |           |=TRUE             |=FALSE         |
                v           v                  |               |
       ----------        ---------             |               |
      | DELIVERY |      | PAYMENT |            |               |
      |          |      | {second)|            |               |
       ----------        ---------             |               |
            |                |                 |               v
             ----------------------------------------------> STOP
  • -*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*
             Figure 31 Valid Combinations of Document Exchanges

Burdett Informational [Page 231] RFC 2801 IOTP/1.0 April 2000

 1) If first IOTP Message of an IOTP Transaction contains an
    Authentication Request then:
    a) IOTP Transaction includes an Authentication Document Exchange
       (see section 9.1.1). (Note 1)
    b) If the last IOTP Message of the Authentication Document
       Exchange includes a TPO Block and an Offer Response Block then:
       i) IOTP Transaction includes a Brand Independent Offer Document
          Exchange (see section 9.1.2.2). (Note 2)
    c) Otherwise, if the last IOTP Message of the Authentication
       Exchange includes a TPO Block but NO Offer Response Block,
       then:
       i) IOTP Transaction includes a Brand Dependent Offer Document
          Exchange (see section 9.1.2.1). (Note 2)
    d) Otherwise (Authentication Status IOTP Message of the
       Authentication Document Exchange contains neither a TPO Block
       but nor an Offer Response Block)
       i) IOTP Transaction consists of just an Authentication Document
          Exchange. (Note 3)
 2) Otherwise (no Authentication Request in first IOTP Message):
    e) IOTP Transaction does not include an Authentication Document
       Exchange (Note 2)
    f) If first IOTP Message contains an Offer Response Block, then:
       i) the IOTP Transaction contains a Brand Independent Offer
          Document Exchange (Note 2)
    g) Otherwise (no Offer Response Block in first IOTP Message):
       i) the IOTP Transaction includes a Brand Dependent Offer
          Document Exchange (Note 2)
 3) If an Offer Response Block exists in any IOTP message then:
    h) If the Offer Response Block contains a Delivery Component then:
       i) If the DelivAndPayResp attribute of the Delivery Component
          is set to True, then:

Burdett Informational [Page 232] RFC 2801 IOTP/1.0 April 2000

          (1) the IOTP Transaction consists of a Payment And Delivery
              Document Exchange (see section 9.1.5) (Note 4)
      ii) otherwise (the DelivAndPayResp attribute of the Delivery
          Component is set to False)
          (1) the IOTP Transaction consists of a Payment Document
              Exchange (see section 9.1.3) followed by a Delivery
              Document Exchange (see section 9.1.4) (Note 4)
    i) otherwise (the Offer Response Block does not contain a Delivery
       Component)
       i) if the Offer Response Block contains just one Payment
          Component, then:
          (1) the IOTP Transaction contains just one Payment Document
              Exchange (Note 5)
      ii) if the Offer Response Block contains two Payment Components,
          then:
          (1) the IOTP Transaction contains two Payment Document
              Exchanges.  The StartAfter attribute of the Payment
              Components is used to indicate which payment occurs
              first (Note 6)
     iii) if the Offer Response Block contains no or more than two
          Payment Components, then there is an error
 4) Otherwise (no Offer Response Block) there is an error.
 The following table indicates the types of IOTP Transactions which
 can validly have the conditions indicated above.
 Note                     IOTP Transaction Validity
 1. Any Payment and Authentication IOTP Transaction
 2. Any Payment and Authentication IOTP Transaction except Baseline
    Authentication
 3. Either Baseline Authentication, or a Baseline Purchase, Refund,
    Deposit, Withdrawal or Value Exchange with a failed Authentication
 4. Baseline Purchase only
 5. Baseline Purchase, Refund, Deposit or Withdrawal

Burdett Informational [Page 233] RFC 2801 IOTP/1.0 April 2000

 6. Baseline Value Exchange only

9.1.13 Combining Authentication Transactions with other Transactions

 In the previous sections an Authentication Document Exchange is shown
 preceding an Offer Document Exchange as part of a single IOTP
 Transaction with the same IOTP Transaction Id.
 It is also possible to run a separate Authentication Transaction at
 any point, even in parallel with another IOTP Transaction. Typically
 this will be used:
 o  by a Consumer to authenticate a Merchant, Payment Handler or a
    Delivery Handler, or
 o  by a Payment Handler or Delivery Handler to authenticate a
    Consumer.
 In outline the basic process consists of:
 o  the Trading Role that decides it wants to carry out an
    authentication of another role suspends the current IOTP
    transaction being carried out
 o  a stand-alone Authentication transaction is then carried out. This
    may, at implementer's option, be linked to the original IOTP
    Transaction using a Related To Component (see section 3.3.3) in
    the Transaction Reference Block.
 o  if the Authentication transaction is successful, then the original
    IOTP Transaction is restarted
 o  if the Authentication fails then the original IOTP Transaction is
    cancelled.
 For example, a Consumer could:
 o  authenticate the Payment Handler for a Payment between receiving
    an Offer Response from a Merchant and before sending the Payment
    Request to that Payment Handler
 o  authenticate a Delivery Handler for a Delivery between receiving
    the Payment Response from a Payment Handler and before sending the
    Delivery Request
 A Payment Handler could authenticate a Consumer after receiving the
 Payment Request and before sending the next Payment related message.

Burdett Informational [Page 234] RFC 2801 IOTP/1.0 April 2000

 A Delivery Handler could authenticate a Consumer after receiving the
 Delivery Request and before sending the Delivery Response.
 Note: Some Payment Methods may carry out an authentication within the
 Payment Exchange. In this case the information required to carry out
 the authentication will be included in Payment Scheme Components.
 In this instance IOTP aware application will not be aware that an
 authentication has occurred since the Payment Scheme Components that
 contain authentication request information will be indistinguishable
 from other Payment Scheme Components.

9.2 Infrastructure Transactions

 Infrastructure Transactions are designed to support inquiries about
 whether or not a transaction has succeeded or a Trading Role's
 servers are operating correctly. There are two types of transaction:
 o  a Transaction Status Inquiry Transaction which provides
    information on the status of an existing or complete IOTP
    transaction, and
 o  Ping Transaction that enables one IOTP aware application to
    determine if the IOTP aware application at another Trading Role is
    operating and verify whether or not signatures can be handled.
 Each of these is described below

9.2.1 Baseline Transaction Status Inquiry IOTP Transaction

 The Baseline IOTP Transaction Status Inquiry provides information on
 the status of an existing or complete IOTP transaction.
 The Trading Blocks used by the Baseline Transaction Status Inquiry
 Transaction are:
 o  an Inquiry Request Trading Block (see section 8.12),
 o  an Inquiry Response Trading Block (see section 8.13)
 o  an optional Signature Block (see section 8.16).
 The Inquiry IOTP Transaction can be used for a variety of reasons.
 For example:
 o  to help in resuming a suspended transaction to determine the
    current state of processing of one of the other roles,

Burdett Informational [Page 235] RFC 2801 IOTP/1.0 April 2000

 o  for a merchant to determine if a payment, delivery, etc., was
    completed.  For example, a Consumer might claim that payment was
    made but no signed IOTP payment receipt was available to prove it.
    If the Merchant makes an inquiry of the Payment Handler then the
    Merchant can determine whether or not payment was made.
 Note: Inquiries on Baseline Ping IOTP Transactions (see section
 9.2.2) are ignored.
 MAKING INQUIRIES OF ANOTHER TRADING ROLE
 One Trading Role may make an inquiry of any other Trading Role at any
 point in time.
 IOTP aware software that supports the Consumer Trading Role may not:
 o  digitally sign a response if requested, since it may not have the
    capability, or
 o  respond to an Inquiry Request at all since it may not be on-line,
    or may consider that the request is not reasonable since, for
    example, the Request was not digitally signed.
 As a guideline:
 o  the Consumer should send a Transaction Status Inquiry Block to a
    Trading Role only after the following events have occurred:
  1. to the Merchant, after sending a TPO Selection Block,
  1. to the Payment Handler, after sending a Payment Request Block,
  1. to the Delivery Handler, after sending a Delivery Request Block,
 o  other Trading Roles should send a Transaction Status Inquiry Block
    to the Consumer only after receiving a message from the Consumer
    and before sending the final "Response" message to the Consumer
 o  there are no restrictions on non-Consumer Trading Roles sending
    Inquiries to other trading roles.
 TRANSACTION STATUS INQUIRY TRANSPORT SESSION
 For a Transaction Status Inquiry on an ongoing transaction a
 different transport session from the ongoing transaction is used. For
 a Transaction Status Inquiry on a past transaction, how the IOTP

Burdett Informational [Page 236] RFC 2801 IOTP/1.0 April 2000

 module on the software at the Trading Role is started upon the
 receipt of Inquiry Request message is defined in each Mapping to
 Transport supplement for IOTP.
 TRANSACTION STATUS INQUIRY ERROR HANDLING
 Errors in a Transaction Status Inquiry can be categorised into one of
 the following three cases:
 o  Business errors (see section 4.2) in the original (inquired)
    messages
 o  Technical errors (see section 4.1) - both IOTP and payment scheme
    specific ones - in the original IOTP (inquired) messages
 o  Technical errors in the message containing the Inquiry Request
    Block itself
 The following outlines what the software should do in each case
 BUSINESS ERRORS IN THE ORIGINAL MESSAGES
 Return an Inquiry Response Block containing the Status Component
 which was last sent to the Consumer Role.
 TECHNICAL ERRORS IN THE ORIGINAL MESSAGES
 Return an Inquiry Response Block containing a Status Component. The
 Status Component should contain a ProcessState attribute set to
 ProcessError. In this case send back an Error Block indicating where
 the error was found in the original message.
 TECHNICAL ERRORS IN THE INQUIRY REQUEST BLOCK
 Return an Error message. That is, send back an Error Block containing
 the Error Code (see section 7.21.2) which describes the nature of the
 error in the Inquiry Request message.
 INQUIRY TRANSACTION MESSAGES
 The following Figure outlines the Baseline IOTP Transaction Status
 Inquiry process.

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*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*

 1st Role
   |  2nd Role

STEP | | 1. The first role decides to inquire on an IOTP Transaction

           by, for example, clicking on the inquiry button of an
           IOTP Aware Application. This will then generate an
           Inquiry Request Block and send it to the appropriate
           Trading Role.
   1 --> 2 INQUIRY REQUEST. IotpMsg: TransRef Block; Signature Block
           (optional); Inquiry Request Block

2. The Trading Role checks the digital signature (if

           present). If the recipient wants to respond, then the
           Trading Role checks the transaction status of the
           transaction that is being inquired upon by using the
           IotpTransId in the Transaction ID Component of the
           Transaction Reference Block, then generates the
           appropriate Inquiry Response Block, sends the message
           back to the 1st Role and stops
   1 <-- 2 INQUIRY RESPONSE. IotpMsg: TransRef Block; Inquiry
           Response Block; Signature Block (Optional)

3. First role checks the Inquiry Response Block and optional

           signature, takes whatever action is appropriate or
           perhaps stops. This may include displaying status
           information to the end user.

*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*

              Figure 32 Baseline Transaction Status Inquiry
 The remainder of this sub-section on the Baseline Transaction Status
 Inquiry IOTP Transaction defines the contents of each Trading Block.
 Note that the term "original transaction" is the transaction which a
 trading role wants to discover some information about.
 TRANSACTION REFERENCE BLOCK
 A Trading Role making an inquiry must use a Transaction Id Component
 (see section 3.3.1) where both the IotpTransId and TransTimeStamp
 attributes are the same as in the Transaction Id Component of the
 original transaction that is being inquired upon. The IotpTransId
 attribute in this component serves as the key in querying the

Burdett Informational [Page 238] RFC 2801 IOTP/1.0 April 2000

 transaction logs maintained at the Trading Role's site. The value of
 the ID attribute of the Message Id Component should be different from
 those of any in the original transaction (see section 3.4.1).
 If up-to-date status information is required then the MsgId
 Component, and in particular the ID attribute for the MsgId Component
 must be different from any other IOTP Message that has been sent by
 the Trading Role. This is required because of the way that
 Idempotency is handled by IOTP (see section 4.5.2.2 Checking/Handling
 Duplicate Messages).
 INQUIRY REQUEST BLOCK
 The Inquiry Request Block (see section 8.12) contains the following
 components:
 o  one Inquiry Type Component (see section 7.18). This identifies
    whether the inquiry is on an offer, payment, or delivery.
 o  zero or one Payment Scheme Components (see section 7.10). This is
    for encapsulating payment scheme specific inquiry messages for
    inquiries on a payment.
 SIGNATURE BLOCK (INQUIRY REQUEST)
 If a signature block is present on the message containing the Inquiry
 Request Block then it may be checked to determine if the Inquiry
 Request is authorised.
 If present, the Inquiry Request Signature Block (see section 8.12)
 contains the following components:
 o  one Signature Component (see section 7.19)
 o  one or more Certificate Components, if required.
 Inquiry Response Blocks should only be generated if the Transaction
 is authorised.
 Note: Digital signatures on an Inquiry Request is only likely to
 occur if the recipient of the request expects the Inquiry Request to
 be signed. In this version of IOTP this will require some kind of
 pre-existing agreement. This means that:
 o  Consumers are unlikely to generate requests with signatures,
    although it is not an error if they do

Burdett Informational [Page 239] RFC 2801 IOTP/1.0 April 2000

 o  the other trading roles may agree that digital signatures are
    required. For example a Payment Handler may require that an
    Inquiry Request is digitally signed by the Merchant so that they
    can check that the request is valid.
 On the other hand if the original transaction to which the Inquiry
 relates was carried out over a secure channel (e.g., [SSL]) then it
 is probably reasonable to presume that if the sender of the Inquiry
 knows the Transaction Id component of the original message (including
 for example the timestamp) then the inquiry is likely to be genuine.
 INQUIRY RESPONSE BLOCK
 The Inquiry Response Block (see section 8.13) contains the following
 components:
 o  one Status Component (see section 7.16). This component holds the
    status information on the inquired transaction,
 o  zero or one Payment Scheme Components. These contain encapsulated
    payment scheme specific inquiry messages for inquiries on payment.
 SIGNATURE BLOCK (INQUIRY RESPONSE)
 If a signature block is present on the message containing the Inquiry
 Response Block then it may be checked by the receiver of the block to
 determine if the Inquiry Response is valid.
 If present, the Inquiry Response Signature Block (see section 8.13)
 contains the following components:
 o one Signature Component (see section 7.19)
 o one or more Certificate Components, if required.
 Note: Digital signatures on an Inquiry Response is only likely to
 occur if the recipient of the response expects the Inquiry Request to
 be signed. In this version of IOTP this will require some kind of
 pre-existing agreement. This means that:
 o  Consumers are unlikely to generate responses with signatures,
    although it is not an error if they do
 o  the other trading roles may agree that digital signatures are
    required. For example a Merchant may require that an Inquiry
    Response is digitally signed by the Payment Handler so that they
    can check that the request response is valid.

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9.2.2 Baseline Ping IOTP Transaction

 The purpose of the Baseline IOTP Ping Transaction is to test basic
 connectivity between the Trading Roles that may take part in an IOTP
 Transaction.
 It enables IOTP aware application software to:
 o  determine if the IOTP aware application at another Trading Role is
    operating, and
 o  verify whether or not the two trading roles signatures can be
    processed.
 For example it can be used by a Merchant to determine if a Payment
 Handler or Delivery Handler is up and running prior to starting a
 Purchase transaction that uses those trading roles.
 The Trading Blocks used by the Baseline Ping IOTP Transaction are:
 o a Ping Request Block (see section 8.14)
 o a Ping Response Block (see section 8.15), and
 o a Signature Block (see section 8.16).
 PING MESSAGES
 The following figure outlines the message flows in the Baseline IOTP
 Ping Transaction.

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*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*

  1st Role
   |  2nd Role

STEP | | 1. The IOTP Aware Application in the first Trading Role

           decides to check whether the counterparty IOTP
           application is up and running. It generates a Ping
           Request Block and optional Signature Block and sends them
           to the second trading role.
   1 --> 2 PING REQUEST. IotpMsg: Trans Ref Block; Signature Block
           (Optional); Ping Request Block

2. The second Trading Role which receives the Ping Request

           Block generates a Ping Response Block and sends it back
           to the sender of the original Ping Request with a
           signature block if required.
   1 <-- 2 PING Response. IotpMsg: Trans Ref Block; Signature Block
           (Optional); Ping Response Block

3. The first Trading Role checks the Ping Response Block and

           takes appropriate action, if necessary

*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*

                    Figure 33 Baseline Ping Messages
 The verification that signatures can be handled is indicated by the
 sender of the Ping Request Block including:
 o  Organisation Components that identify itself and the intended
    recipient of the Ping Request Block, and
 o  a Signature Block that signs data in the Ping Request.
 In this way the receiver of the Ping Request:
 o  knows who is sending the Ping Request and can therefore verify the
    Signature on the Request, and
 o  knows who to generate a signature for on the Ping Response.
 Note that a Ping Request:
 o  does not affect any on-going transaction

Burdett Informational [Page 242] RFC 2801 IOTP/1.0 April 2000

 o  does NOT initiate an IOTP transaction, unlike other IOTP
    transaction messages such as TPO or Transaction Status Inquiry.
 All IOTP aware applications must return a Ping Response message to
 the sender of a Ping Request message when it is received.
 A Baseline IOTP Ping request can also contain an optional Signature
 Block. IOTP aware applications can, for example, use the Signature
 Block to check the recipient of a Ping Request can successfully
 process and check signatures it has received.
 For each Baseline Ping IOTP Transaction, each IOTP role shall
 establish a different transport session from other IOTP transactions.
 Any IOTP Trading Role can send a Ping request to any other IOTP
 Trading Role at any time it wants. A Ping message has its own
 IotpTransId, which is different from other IOTP transactions.
 The remainder of this sub-section on the Baseline Ping IOTP
 Transaction defines the contents of each Trading Block.
 TRANSACTION REFERENCE BLOCK
 The IotpTransId of a Ping transaction should be different from any
 other IOTP transaction.
 PING REQUEST BLOCK
 If the Ping Transaction is anonymous then no Organisation Components
 are included in the Ping Request Block (see section 8.7).
 If the Ping Transaction is not anonymous then the Ping Request Block
 contains Organisation Components for:
 o  the sender of the Ping Request Block, and
 o  the verifier of the Signature Component
 If Organisation Components are present, then it indicates that the
 sender of the Ping Request message has generated a Signature Block.
 The signature block must be verified by the Trading Role that
 receives the Ping Request Block.
 SIGNATURE BLOCK (PING REQUEST)
 The Ping Request Signature Block (see section 8.16) contains the
 following components:

Burdett Informational [Page 243] RFC 2801 IOTP/1.0 April 2000

 o  one Signature Component (see section 7.19)
 o  one or more Certificate Components, if required.
 PING RESPONSE BLOCK
 The Ping Response Block (see section 8.15) contains the following
 component:
 o  the Organisation Component of the sender of the Ping Response
    message
 If the Ping Transaction is not anonymous then the Ping Response
 additionally contains:
 o  copies of the Organisation Components contained in the Ping
    Request Block.
 SIGNATURE BLOCK (PING RESPONSE)
 The Ping Response Signature Block (see section 8.16) contains the
 following components:
 o  one Signature Component (see section 7.19)
 o  one or more Certificate Components, if required.

10. Retrieving Logos

 This section describes how to retrieve logos for display by IOTP
 aware software using the Logo Net Locations attribute contained in
 the Brand Element (see section 7.7.1) and the Organisation Component
 (see section 7.6).
 The full address of a logo is defined as follows:  Logo_address ::=
 Logo_net_location "/" Logo_size Logo_color_depth ".gif"
 Where:
 o  Logo_net_location is obtained from the LogoNetLocn attribute in
    the Brand Element (see section 7.7.1) or the Organisation
    Component. Note that:
  1. the content of this attribute is dependent on the Transport

Mechanism (such as HTTP) that is used. See the Transport

       Mechanism supplement,

Burdett Informational [Page 244] RFC 2801 IOTP/1.0 April 2000

  1. implementers should check that if the rightmost character of

Logo Net Location is set to right-slash "/" then another, right

       slash should not be included when generating the Logo Address,
 o  Logo_size identifies the size of the logo,
 o  Logo_color_depth identifies the colour depth of the logo
 o  "gif" indicates that the logos are in "gif" format
 Logo_size and Logo_color_depth are specified by the implementer of
 the IOTP software that is retrieving the logo depending on the size
 and colour that they want to use.

10.1 Logo Size

 There are five standard sizes for logos. The sizes in pixels and the
 corresponding values for Logo Size are given in the table below.
         Size in     Logo Size
         Pixels        Value
      32 x 32 or   exsmall
      32 x 20
      53 x 33      small
      103 x 65     medium
      180 x 114    large
      263 x 166    exlarge

10.2 Logo Color Depth

 There are three standard colour depths. The colour depth (including
 bits per pixel) and the corresponding value for Logo_Color_Depth are
 given in the table below.
              Color Depth          Logo Color
           (bits per pixel)        Depth Value
       4 (16 colors)            4
       8 (256 colors)           nothing
       24 (16 million colors)   24

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 Note that if Logo Color Depth is omitted then a logo with the default
 colour depth of 256 colours will be retrieved.

10.3 Logo Net Location Examples

 If Logo Net Location was set to "ftp://logos.xzpay.com", then:
 o  "ftp://logos.xzpay.com/medium.gif" would retrieve a medium size
    256 colour logo
 o  "http://logos.xzpay.com/small4.gif" would retrieve a small size 16
    colour logo
 Note: Organisations which make logos available for use with IOTP
 should always make available "small" and "medium" size logos and use
 the "gif" format.

11. Brands

 This section contains:
 o  a definition of Brands and an outline of Brand Selection using
    Brand Lists, and
 o  some XML examples of Brand Lists

11.1 Brand Definitions and Brand Selection

 One of the key features of IOTP is the ability for a merchant to
 offer a list of Brands from which a consumer may make a selection.
 This section provides an overview of what is involved and provides
 guidance on how selection of a brand and associated payment
 instrument can be carried out by a Consumer. It covers:
 o  definitions of Payment Instruments and Brands - what are Payment
    Instruments and Brands in an IOTP context. Further categorises
    Brands as optionally a "Dual Brand" or a "Promotional Brand",
 o  identification and selection of Promotional Brands - Promotional
    Brands offer a Consumer some additional benefit, for example
    loyalty points or a discount. This means that both Consumers and
    Merchant must be able to correctly identify that a valid
    Promotional Brand is being used.
 Also see the following sections:

Burdett Informational [Page 246] RFC 2801 IOTP/1.0 April 2000

 o  Brand List Component (section 7.7) which contains definitions of
    the XML elements which contain the list of Brands offered by a
    Merchant to a Consumer, and
 o  Brand Selection Component (section 7.8) for details of how a
    Consumer records the Brand, currency, amount and payment protocol
    that was selected.

11.1.1 Definition of Payment Instrument

 A Payment Instrument is the means by which a Consumer pays for goods
 or services offered by a Merchant. It can be, for example:
 o  a credit card such as MasterCard or Visa;
 o  a debit card such as MasterCard's Maestro;
 o  a smart card based electronic cash payment instrument such as a
    Mondex Card, a GeldKarte card or a Visa Cash card
 o  a software based electronic payment account such as a CyberCash or
    DigiCash account.
 Most Payment Instruments have a number, typically an account number,
 by which the Payment Instrument can be identified.

11.1.2 Definition of Brand

 A Brand is the mark which identifies a particular type of Payment
 Instrument. A list of Brands are the payment options which are
 presented by the Merchant to the Consumer and from which the Consumer
 makes a selection. Each Brand may have a different Payment Handler.
 Examples of Brands include:
 o  payment association and proprietary Brands, for example
    MasterCard, Visa, American Express, Diners Club, Mondex,
    GeldKarte, CyberCash, etc.
 o  promotional brands (see below). These include:
  1. store brands, where the Payment Instrument is issued to a

Consumer by a particular Merchant, for example Walmart, Sears,

       or Marks and Spencer (UK)
  1. cobrands, for example American Advantage Visa, where an

Organisation uses their own brand in conjunction with,

       typically, a payment association Brand.

Burdett Informational [Page 247] RFC 2801 IOTP/1.0 April 2000

11.1.3 Definition of Dual Brand

 A Dual Brand means that a single payment instrument may be used as if
 it were two separate Brands. For example there could be a single
 Japanese "UC" MasterCard which can be used as either a UC card or a
 regular MasterCard. The UC card Brand and the MasterCard Brand could
 each have their own separate Payment Handlers. This means that:
 o  the merchant treats, for example "UC" and "MasterCard" as two
    separate Brands when offering a list of Brands to the Consumer,
 o  the consumer chooses a Brand, for example either "UC" or
    "MasterCard,
 o  the consumer IOTP aware application determines which Payment
    Instrument(s) match the chosen Brand, and selects, perhaps with
    user assistance, the correct Payment Instrument to use.
 Note: Dual Brands need no special treatment by the Merchant and
 therefore no explicit reference is made to Dual Brands in the DTD.
 This is because, as far as the Merchant is concerned, each Brand in a
 Dual Brand is treated as a separate Brand. It is at the Consumer,
 that the matching of a Brand to a Dual Brand Payment Instrument needs
 to be done.

11.1.4 Definition of Promotional Brand

 A Promotional Brand means that, if the Consumer pays with that Brand,
 then the Consumer will receive some additional benefit which can be
 received in two ways:
 o  at the time of purchase. For example if a Consumer pays with a
    "Walmart MasterCard" at a Walmart web site, then a 5% discount
    might apply, which means the consumer actually pays less,
 o  from their Payment Instrument (card) issuer when the payment
    appears on their statement. For example loyalty points in a
    frequent flyer scheme could be awarded based on the total payments
    made with the Payment Instrument since the last statement was
    issued.
 Note that:
 o  the first example (obtaining the benefit at the time of purchase),
    requires that:
  1. the Consumer is informed of the benefits which arise if that

Brand is selected

Burdett Informational [Page 248] RFC 2801 IOTP/1.0 April 2000

  1. if the Brand is selected, the Merchant changes the relevant

IOTP Components in the Offer Response to reflect the correct

       amount to be paid
 o  the second (obtaining a benefit through the Payment Instrument
    issuer) does not require that the Offer Response is changed
 o  each Promotional Brand should be identified as a separate Brand in
    the list of Brands offered by the Merchant. For example:
    "Walmart", "Sears", "Marks and Spencer" and "American Advantage
    Visa", would each be a separate Brand.

11.1.5 Identifying Promotional Brands

 There are two problems which need to handled in identifying
 Promotional Brands:
 o  how does the Merchant or their Payment Handler positively identify
    the promotional brand being used at the time of purchase
 o  how does the Consumer reliably identify the correct promotional
    brand from the Brand List presented by the Merchant
 The following is a description of how this could be achieved.
 Note: Please note that the approach described here is a model
 approach that solves the problem. Other equivalent methods may be
 used.

11.1.5.1 Merchant/Payment Handler Identification of Promotional Brands

 Correct identification that the Consumer is paying using a
 Promotional Brand is important since a Consumer might fraudulently
 claim to have a Promotional Brand that offers a reduced payment
 amount when in reality they do not.
 Two approaches seem possible:
 o  use some feature of the Payment Instrument or the payment method
    to positively identify the Brand being used. For example, the SET
    certificate for the Brand could be used, if one is available, or
 o  use the Payment Instrument (card) number to look up information
    about the Payment Instrument on a Payment Instrument issuer
    database to determine if the Payment Instrument is a promotional
    brand.

Burdett Informational [Page 249] RFC 2801 IOTP/1.0 April 2000

 Note that:
 o  the first assumes that SET is available.
 o  the second is only possible if the Merchant, or alternatively the
    Payment Handler, has access to card issuer information.
 IOTP does not provide the Merchant with Payment Instrument
 information (e.g., a card or account number). This is only sent as
 part of the encapsulated payment protocol to a Payment Handler. This
 means that:
 o  the Merchant would have to assume that the Payment Instrument
    selected was a valid Promotional Brand, or
 o  the Payment Handler would have to check that the Payment
    Instrument was for the valid Promotional Brand and fail the
    payment if it was not.
 A Payment Handler checking that a brand is a valid Promotional Brand
 is most likely if the Payment Handler is also the Card Issuer.

11.1.5.2 Consumer Selection of Promotional Brands

 Two ways by which a Consumer can correctly select a Promotional Brand
 are:
 o  the Consumer visually matching a logo for the Promotional Brand
    which has been provided to the Consumer by the Merchant,
 o  the Consumer's IOTP aware application matching a code for the
    Promotional Brand which the application has registered against a
    similar code contained in the list of Brands offered by the
    Merchant.
 In the latter case, the code contained in the Consumer wallet must
 match exactly the code in the list offered by the Merchant otherwise
 no match will be found. Ways in which the Consumer's IOTP Aware
 Application could obtain such a code include:
 o  the Consumer types the code in directly. This is error prone and
    not user friendly, also the consumer needs to be provided with the
    code.  This approach is not recommended,
 o  using one of the Brand Identifiers defined by IOTP and pre-loaded
    into the Consumers IOTP Aware application or wallet by the
    developer of the Wallet,

Burdett Informational [Page 250] RFC 2801 IOTP/1.0 April 2000

 o  using some information contained in the software or other data
    associated with the Payment Instrument. This could be:
  1. a SET certificate for Brands which use this payment method
  1. a code provided by the payment software which handles the

particular payment method, this could apply to, for example,

       GeldKarte, Mondex, CyberCash and DigiCash,
 o  the consumer making an initial "manual" link between a Promotional
    Brand in the list of Brands offered by the Merchant and an
    individual Payment Instrument, the first time the promotional
    brand is used. The IOTP Aware application would then "remember"
    the code for the Promotional Brand for use in future purchases.

11.1.5.3 Consumer Software Brand Id recommendation

 New Brand Ids are allocated under IANA procedures (see section 12
 IANA Considerations). Which also contains an initial list of Brand
 Identifiers.
 It is recommended that implementers of consumer IOTP aware
 applications (e.g., software wallets) pre-load their software with
 the then current set of Brand Ids and provide a method by which they
 can be updated. For example, by going to the software developer's web
 site.

11.2 Brand List Examples

 This example contains three examples of the XML for a Brand List
 Component. It covers:
 o  a simple credit card based example
 o  a credit card based brand list including promotional credit card
    brands, and
 o  a complex electronic cash based brand list
 Note that:
 o  brand lists can be as complex or as simple as required
 o  all example techniques described in this appendix can be included
    in one brand list.

Burdett Informational [Page 251] RFC 2801 IOTP/1.0 April 2000

11.2.1 Simple Credit Card Based Example

 This is a simple example involving:
 o  only major credit card payment brands
 o  a single price in a single currency
 o  a single Payment Handler, and
 o  a single payment protocol
 <BrandList ID='M1.2'
   XML:Lang='us-en'
   ShortDesc='Purchase book including s&h'
   PayDirection='Debit' >
   <Brand ID ='M1.30'
     BrandId='MasterCard'
     BrandName='MasterCard Credit'
     BrandLogoNetLocn='ftp://otplogos.mastercard.com/mastercardcredit'
     ProtocolAmountRefs='M1.33'>
   </Brand>
   <Brand ID ='M.31'
     BrandId='Visa'
     BrandName='Visa Credit'
     BrandLogoNetLocn='ftp://otplogos.visa.com/visacredit'
     ProtocolAmountRefs='M1.33'>
   </Brand>
   <Brand ID ='M1.32'
     BrandId='AmericanExpress'
     BrandName='American Express'
     BrandLogoNetLocn='ftp://otplogos.amex.com'
     ProtocolAmountRefs ='M1.33' >
   </Brand >
   <ProtocolAmount ID ='M1.33'
     PayProtocolRef='M1.35'
     CurrencyAmountRefs='M1.34'>
   </ProtocolAmount>
   <CurrencyAmount ID ='M1.34'
     Amount='10.95'
     CurrCode='USD'/>
   <PayProtocol ID ='M1.35'
     ProtocolId='SCCD1.0'
     ProtocolName='Secure Channel Credit/Debit'
     PayReqNetLocn='http://www.example.com/etill/sccd1' >
   </PayProtocol>
 </BrandList>

Burdett Informational [Page 252] RFC 2801 IOTP/1.0 April 2000

11.2.2 Credit Card Brand List Including Promotional Brands

 An example of a Credit Card based Brand List follows. It includes:
 o  two ordinary card association brands and two promotional credit
    card brands. The promotional brands consist of one loyalty based
    (British Airways MasterCard) which offers additional loyalty
    points and one store based (Walmart) which offers a discount on
    purchases over a certain amount
 o  two payment protocols:
  1. SET (Secure Electronic Transactions) see [SET], and
  1. SCCD (Secure Channel Credit Debit) see [SCCD].

<BrandList ID='M1.2'

 XML:Lang='us-en'
 ShortDesc='Purchase ladies coat'
 PayDirection='Debit' >
 <Brand ID ='M1.3'
   BrandId='MasterCard'
   BrandName='MasterCard Credit'
   BrandLogoNetLocn='ftp://otplogos.mastercard.com'
   ProtocolAmountRefs='M1.7 M1.8'>
   <ProtocolBrand ProtocolId='SET1.0' ProtocolBrandId='MasterCard:'>
   </ProtocolBrand>
 </Brand>
 <Brand ID ='M1.4'
   BrandId='Visa'
   BrandName='Visa Credit'
   BrandLogoNetLocn='ftp://otplogos.visa.com'
   ProtocolAmountRefs='M1.7 M1.8'>
   <ProtocolBrand ProtocolId='SET1.0' ProtocolBrandId='Visa:'>
   </ProtocolBrand>
 </Brand>
 <Brand ID ='M1.5'
   BrandId='BritishAirwaysMC'
   BrandName='British Airways MasterCard'
   BrandLogoNetLocn='ftp://otplogos.britishairways.co.uk'
   BrandNarrative='Double air miles with British Airways MasterCard'
   ProtocolAmountRefs ='M1.7 M1.8' >
   <ProtocolBrand ProtocolId='SET1.0' ProtocolBrandId='MasterCard:BA'>
   </ProtocolBrand>
 </Brand >
 <Brand ID ='M1.6'
   BrandId='Walmart'
   BrandName='Walmart Store Card'

Burdett Informational [Page 253] RFC 2801 IOTP/1.0 April 2000

   BrandLogoNetLocn='ftp://otplogos.walmart.com'
   BrandNarrative='5% off with your Walmart Card
                 on purchases over $150'
   ProtocolAmountRefs='M1.8'>
 </Brand>
 <ProtocolAmount ID ='M1.7'
   PayProtocolRef='M1.10'
   CurrencyAmountRefs='M1.9' >
   <PackagedContent Transform="BASE64">
      238djqw1298erh18dhoire
   </PackagedContent>
 </ProtocolAmount>
 <ProtocolAmount ID ='M1.8'
   PayProtocolRef='M1.11'
   CurrencyAmountRefs='M1.9' >
   <PackagedContent Transform="BASE64">
      238djqw1298erh18dhoire
   </PackagedContent>
 </ProtocolAmount>
 <CurrencyAmount ID ='M1.9'
   Amount='157.53'
   CurrCode='USD'/>
 <PayProtocol ID ='M1.10'
   ProtocolId='SET1.0'
   ProtocolName='Secure Electronic Transaction Version 1.0'
   PayReqNetLocn='http://www.example.com/etill/set1' >
   <PackagedContent Transform="BASE64">
     8ueu26e482hd82he82
   </PackagedContent>
 </PayProtocol>
 <PayProtocol ID ='M1.11'
   ProtocolId='SCCD1.0'
   ProtocolName='Secure Channel Credit/Debit'
   PayReqNetLocn='http://www.example.com/etill/sccd1' >
   <PackagedContent Transform="BASE64">
      82hd82he8226e48ueu
   </PackagedContent>
 </PayProtocol>
</BrandList>

11.2.3 Brand Selection Example

 In order to pay by 'British Airways' MasterCard using the example
 above using SET and therefore getting double air miles, the Brand
 Selection would be:
 <BrandSelection ID='C1.2'

Burdett Informational [Page 254] RFC 2801 IOTP/1.0 April 2000

   BrandListRef='M1.3'
   BrandRef='M1.5'
   ProtocolAmountRef='M1.7'
   CurrencyAmountRef='M1.9' >
 </BrandSelection>

11.2.4 Complex Electronic Cash Based Brand List

 The following is an fairly complex example which includes:
 o  payments using either Mondex, GeldKarte, CyberCash or DigiCash
 o  in currencies including US dollars, British Pounds, Italian Lira,
    German Marks and Canadian Dollars
 o  a discount on the price if the payment is made in Mondex using
    British pounds or US dollars, and
 o  more than one Payment Handler is used for payments involving
    Mondex or CyberCash
 o  support for more than one version of a CyberCash CyberCoin payment
    protocol.
 <BrandList ID='M1.2'
   XML:Lang='us-en'
   ShortDesc='Company report on XYZ Co'
   PayDirection='Debit' >
   <Brand ID ='M1.13'
     BrandId='Mondex'
     BrandName='Mondex Electronic Cash'
     BrandLogoNetLocn='ftp://otplogos.mondex.com'
     ProtocolAmountRefs='M1.17 M1.18'>
   </Brand>
   <Brand ID ='M1.14'
     BrandId='GeldKarte'
     BrandName='GeldKarte Electronic Cash'
     BrandLogoNetLocn='ftp://otplogos.geldkarte.co.de'
     ProtocolAmountRefs='M1.19'>
   </Brand>
   <Brand ID ='M1.15'
     BrandId='CyberCoin'
     BrandName='CyberCoin Eletronic Cash'
     BrandLogoNetLocn='http://otplogos.cybercash.com'
     ProtocolAmountRefs ='M1.20' >
   </Brand >
   <Brand ID ='M1.16'
     BrandId='DigiCash'

Burdett Informational [Page 255] RFC 2801 IOTP/1.0 April 2000

     BrandName='DigiCash Electronic Cash'
     BrandLogoNetLocn='http://otplogos.digicash.com'
     BrandNarrative='5% off with your Walmart Card
                   on purchases over $150'
     ProtocolAmountRefs='M1.22'>
   </Brand>
   <ProtocolAmount ID ='M1.17'
     PayProtocolRef='M1.31'
     CurrencyAmountRefs='M1.25 M1.29'>
   </ProtocolAmount>
   <ProtocolAmount ID ='M1.18'
     PayProtocolRef='M1.32'
     CurrencyAmountRefs='M1.26 M1.27 M1.28 M1.30'>
   </ProtocolAmount>
   <ProtocolAmount ID ='M1.19'
     PayProtocolRef='M1.35'
     CurrencyAmountRefs='M1.28'>
   </ProtocolAmount>
   <ProtocolAmount ID ='M1.20'
     PayProtocolRef='M1.34 M1.33'
     CurrencyAmountRefs='M1.23 M1.24 M1.27 M1.28 M1.29 M1.30'>
   </ProtocolAmount>
   <ProtocolAmount ID ='M1.21'
     PayProtocolRef='M1.36'
     CurrencyAmountRefs='M1.23 M1.24 M1.27 M1.28 M1.29 M1.30'>
   </ProtocolAmount>
   <CurrencyAmount ID ='M1.23'
     Amount='20.00'
     CurrCode='USD'/>
   <CurrencyAmount ID ='M1.24'
     Amount='12.00'
     CurrCode='GBP'/>
   <CurrencyAmount ID ='M1.25'
     Amount='19.50'
     CurrCode='USD'/>
   <CurrencyAmount ID ='M1.26'
     Amount='11.75'
     CurrCode='GBP'/>
   <CurrencyAmount ID ='M1.27'
     Amount='36.00'
     CurrCode='DEM'/>
   <CurrencyAmount ID ='M1.28'
     Amount='100.00'
     CurrCode='FFR'/>
   <CurrencyAmount ID ='M1.29'
     Amount='22.00'
     CurrCode='CAD'/>
   <CurrencyAmount ID ='M1.30'

Burdett Informational [Page 256] RFC 2801 IOTP/1.0 April 2000

     Amount='15000'
     CurrCode='ITL'/>
   <PayProtocol ID ='M1.31'
     ProtocolId='MXv1.0'
     ProtocolName='Mondex IOTP Protocol Version 1.0'
     PayReqNetLocn='http://www.mxbankus.com/etill/mx' >
   </PayProtocol>
   <PayProtocol ID ='M1.32'
     ProtocolId='MXv1.0'
     ProtocolName='Mondex IOTP Protocol Version 1.0'
     PayReqNetLocn='http://www.mxbankuk.com/vserver' >
   </PayProtocol>
   <PayProtocol ID ='M1.33'
     ProtocolId='Ccashv1.0'
     ProtocolName='CyberCoin Version 1.0'
     PayReqNetLocn='http://www.cybercash.com/ccoin' >
   </PayProtocol>
   <PayProtocol ID ='M1.34'
     ProtocolId='CCashv2.0'
     ProtocolName='CyberCoin Version 2.0'
     PayReqNetLocn='http://www.cybercash.com/ccoin' >
   </PayProtocol>
   <PayProtocol ID ='M1.35'
     ProtocolId='GKv1.0'
     ProtocolName='GeldKarte Version 1.0'
     PayReqNetLocn='http://www.example.com/pgway' >
   </PayProtocol>
   <PayProtocol ID ='M1.36'
     ProtocolId='DCashv1.0'
     ProtocolName='DigiCash Protocol Version 1.0'
     PayReqNetLocn='http://www.example.com/digicash' >
   </PayProtocol>
   </BrandList>

12. IANA Considerations

 This section describes the codes that are controlled by IANA, and
 also how new codes can be created for testing purposes that are not
 controlled by IANA.

12.1 Codes Controlled by IANA

 To help ensure interoperability, there is a need for codes used by
 IOTP to be maintained in a controlled environment so that their
 meaning and usage are well defined and duplicate codes avoided.
 [IANA] is the mechanism to be used for this purpose as described in
 RFC 2434.

Burdett Informational [Page 257] RFC 2801 IOTP/1.0 April 2000

 The element types and attributes names to which this procedure
 applies is shown in the table below together with the initial values
 that are valid for these attributes.
 Note that:
 o  the IETF Trade mailing list's email address is ietf-
    trade@elistx.com
 o  "Designated Experts" (see [IANA]) are appointed by the IESG.
   Element Type/                     Attribute Values
   Attribute Name
 Algorithm/         "sha1" - indicates that a [SHA1] authentication
 Name               will apply
 (When Algorithm
 is a child of an   "signature" - indicates that authentication
 AuthReq            consists of the generation of a digital signature.
 Component)
                    "Pay:ppp" where "ppp" may be set to any valid
                    value for "iotpbrand" (see below)
                    With the exception of Algorithms that begin with
                    "pay:", new values are allocated following review
                    on the IETF Trade mailing list and by the
                    Designated Expert.
 Note:     The Algorithm element is likely to be eventually defined
 within the [DSIG] name space. It is likely that the maintenance
 procedure defined here may need to vary over time, as the DSIG
 proposals become more widely adopted.
   Element Type/                     Attribute Values
   Attribute Name
 Brand/BrandId      The following list of initial BrandIds have been
                    taken from those Organisations that have applied
                    for SET certificates as at 1st June 1999:
                    "Amex" - American Express
                    "Dankort" - Dankort
                    "JCB" - JCB
                    "Maestro" - Maestro

Burdett Informational [Page 258] RFC 2801 IOTP/1.0 April 2000

                    "MasterCard" - MasterCard
                    "NICOS" - NICOS
                    "VISA" - Visa
                    In addition the following Brand Id values are
                    defined:
                    "Mondex"
                    "GeldKarte"
                    New values of BrandId must be announced to the
                    IETF Trade mailing list and, if there are no
                    objections within three weeks, are allocated on a
                    "first come first served" basis.
 CurrencyAmount/    Currency codes are dependent on CurrCodeType (see
 CurrCode           below).
                    If CurrCodeType is "ISO4217-A" then the currency
                    code is an alphabetic currency code as defined by
                    [ISO4217].
                    If CurrCodeType is "IOTP" then new values must be
                    announced to the IETF Trade mailing list and, if
                    there are no objections within three weeks, are
                    allocated on a "first come first served" basis.
 Note:     The Currency Code Type of IOTP, is designed to allow the
 support of "new" psuedo currencies such as loyalty or frequent flyer
 points. At the time of writing this specification, no currency codes
 of this type have been defined.
   Element Type/                     Attribute Values
   Attribute Name
 CurrencyAmount/    "ISO4217-A"
 CurrCodeType
                    "IOTP"
                    New values of CurrCodeType attribute are allocated
                    following review on the IETF Trade mailing list
                    and by the Designated Expert.
 DeliveryData/      "Post"
 DelivMethod

Burdett Informational [Page 259] RFC 2801 IOTP/1.0 April 2000

                    "Web"
                    "Email"
                    New values of Delivery Method attribute are
                    allocated following review on the IETF Trade
                    mailing list and by the Designated Expert. This
                    may require the publication of additional
                    documentation to describe how the delivery method
                    is used.
 PackagedContent/   "PCDATA"
 Content
                    "MIME"
                    "MIME:mimetype" (where mimetype must be the same
                    as content-type as defined by [MIME] )
                    "XML"
                    If the Content attribute is of the form
                    "MIME"mimetype", then control of new values for
                    "mimetype" is as defined in [MIME].
                    Otherwise, new values of the Content attribute are
                    allocated following review on the IETF Trade
                    mailing list and by the Designated Expert. This
                    may require the publication of additional
                    documentation to describe how the new attribute is
                    used within a Packaged Content element.
 RelatedTo/         "IotpTransaction"
 RelationshipType
                    "Reference"
                    New values of the RelationshipType attribute are
                    allocated following review on the IETF Trade
                    Working Group mailing list and by the Designated
                    Expert. This may require the publication of
                    additional documentation to describe how the
   Element Type/                     Attribute Values
   Attribute Name
                    delivery method is used.
 Status/            Offer
 StatusType
                    Payment

Burdett Informational [Page 260] RFC 2801 IOTP/1.0 April 2000

                    Delivery
                    Authentication
                    Unidentified
                    New values of the Status Type attribute are
                    allocated following:
                     o publication to the IETF Trade Working Group,
                       of an RFC describing the Trading Exchange,
                       Trading Roles and associated components that
                       relate to the Status, and
                     o review of the document on the IETF Trade
                       mailing list and by the Designated Expert.
 Note: The document describing new values for the Status Type
 attribute may be combined with documents that describe new Trading
 Roles and types of signatures (see below).
 TradingRole/       "Consumer"
 TradingRole
                    "Merchant"
                    "PaymentHandler"
                    "DeliveryHandler"
                    "DelivTo"
                    "CustCare"
                    New values of the Trading Role attribute are
                    allocated following:
                     o publication to the IETF Trade Working Group,
                       of an RFC describing the Trading Exchange,
                       Trading Roles and associated components that
                       relate to the Trading Role, and
                     o review of the document on the IETF Trade
                       mailing list and by the Designated Expert.
 Note: The document describing new values for the Trading Role
 attribute may be
   Element Type/                     Attribute Values
   Attribute Name
                                 combined with documents that describe
                                 new Status Types (see above) and
                                 types of signatures (see below).

Burdett Informational [Page 261] RFC 2801 IOTP/1.0 April 2000

 TransId/           "BaselineAuthentication"
 IotpTransType
                    "BaselineDeposit"
                    "BaselinePurchase"
                    "BaselineRefund"
                    "BaselineWithdrawal"
                    "BaselineValueExchange"
                    "BaselineInquiry"
                    "BaselinePing"
                    New values of the IotpTransType attribute are
                    allocated following:
                     o publication to the IETF Trade mailing list, of
                       an RFC describing the new IOTP Transaction, and
                     o review of the document on the IETF Trade
                       Working Group mailing list and by the
                       Designated Expert.
 Attribute/ Content
 (see Signature
                    "OfferResponse"
 Component)         "PaymentResponse"
                    "DeliveryResponse"
                    "AuthenticationRequest"
                    "AuthenticationResponse"
                    "PingRequest"
                    "PingResponse"
                    New values of the code that define the type of a
                    signature are allocated following:
                     o publication to the IETF Trade Working Group,
                       of an RFC describing the Trading Exchange where
                       the signature is being used, and
                     o review of the document on the IETF Trade
                       mailing list and by the Designated Expert.

Burdett Informational [Page 262] RFC 2801 IOTP/1.0 April 2000

   Element Type/                     Attribute Values
   Attribute Name
 Note: The document describing new values for the types of signatures
 may be combined with documents that describe new Status Types and
 Trading Roles (see above).

12.2 Codes not controlled by IANA

 In addition to the formal development and registration of codes as
 described above, there is still a need for developers to experiment
 using new IOTP codes. For this reason, "user defined codes" may be
 used to identify additional values for the codes contained within
 this specification without the need for them to be registered with
 IANA.
 The definition of a user defined code is as follows:
 user_defined_code ::= ( "x-" | "X-" ) NameChar (NameChar)*
   NameChar           NameChar has the same definition as the [XML]
                      definition of NameChar
 Use of domain names (see [DNS]) to make user defined codes unique is
 recommended although this method cannot be relied upon.

13. Internet Open Trading Protocol Data Type Definition

 This section contains the XML DTD for the Internet Open Trading
 Protocols.

Burdett Informational [Page 263] RFC 2801 IOTP/1.0 April 2000

 <!--
 ******************************************************
 *                                                    *
 * INTERNET OPEN TRADING PROTOCOL VERSION 1.0 DTD     *
 * Filename: ietf.org/rfc/rfc2801.dtd                 *
 *                                                    *
 * Changes from version 07 (iotp-v1.0-protocol-07.dtd)*
 *   - NO CHANGES                                     *
 *                                                    *
 *                                                    *
 *                                                    *
 *                                                    *
 * Copyright Internet Engineering Task Force 1998-2000*
 *                                                    *
 ******************************************************
  • *
  • IOTP MESSAGE DEFINITION *
  • *
 <!ELEMENT IotpMessage
    ( TransRefBlk,
      IotpSignatures?,
      ErrorBlk?,
      ( AuthReqBlk |
        AuthRespBlk |
        AuthStatusBlk |
        CancelBlk |
        DeliveryReqBlk |
        DeliveryRespBlk |
        InquiryReqBlk |
        InquiryRespBlk |
        OfferRespBlk |
        PayExchBlk |
        PayReqBlk |
        PayRespBlk |
        PingReqBlk |
        PingRespBlk |
        TpoBlk |
        TpoSelectionBlk
      )*
    ) >
 <!ATTLIST IotpMessage
   xmlns              CDATA
    'iotp:ietf.org/iotp-v1.0' >

Burdett Informational [Page 264] RFC 2801 IOTP/1.0 April 2000

 <!--
 ******************************************************
 * TRANSACTION REFERENCE BLOCK DEFINITION             *
 ******************************************************
  -->
 <!ELEMENT TransRefBlk (TransId, MsgId, RelatedTo*) >
 <!ATTLIST TransRefBlk
  ID                 ID      #REQUIRED >
 <!ELEMENT TransId EMPTY >
 <!ATTLIST TransId
  ID                 ID      #REQUIRED
  Version            NMTOKEN #FIXED '1.0'
  IotpTransId        CDATA   #REQUIRED
  IotpTransType      CDATA   #REQUIRED
  TransTimeStamp     CDATA   #REQUIRED >
 <!ELEMENT MsgId EMPTY >
 <!ATTLIST MsgId
  ID                 ID      #REQUIRED
  RespIotpMsg        NMTOKEN #IMPLIED
  xml:lang           NMTOKEN #REQUIRED
  LangPrefList       NMTOKENS #IMPLIED
  CharSetPrefList    NMTOKENS #IMPLIED
  SenderTradingRoleRef NMTOKEN #IMPLIED
  SoftwareId         CDATA   #REQUIRED
  TimeStamp          CDATA   #IMPLIED >
 <!ELEMENT RelatedTo (PackagedContent) >
 <!ATTLIST RelatedTo
  ID                 ID      #REQUIRED
  xml:lang           NMTOKEN #REQUIRED
  RelationshipType   NMTOKEN #REQUIRED
  Relation           CDATA   #REQUIRED
  RelnKeyWords       NMTOKENS #IMPLIED >
 <!--
 ******************************************************
 * Packaged Content Common Element                    *
 ******************************************************
  -->

Burdett Informational [Page 265] RFC 2801 IOTP/1.0 April 2000

 <!ELEMENT PackagedContent (#PCDATA) >
 <!ATTLIST PackagedContent
  Name             CDATA     #IMPLIED
  Content          NMTOKEN   "PCDATA"
  Transform (NONE|BASE64)    "NONE" >
 <!--
 ******************************************************
 * TRADING COMPONENTS                                 *
 ******************************************************
  -->
 <!-- PROTOCOL OPTIONS COMPONENT -->
 <!ELEMENT ProtocolOptions EMPTY >
 <!ATTLIST ProtocolOptions
  ID                 ID      #REQUIRED
  xml:lang           NMTOKEN #REQUIRED
  ShortDesc          CDATA   #REQUIRED
  SenderNetLocn      CDATA   #IMPLIED
  SecureSenderNetLocn CDATA  #IMPLIED
  SuccessNetLocn     CDATA   #REQUIRED >
 <!-- AUTHENTICATION DATA COMPONENT -->
 <!ELEMENT AuthReq (Algorithm, PackagedContent*)>
 <!ATTLIST AuthReq
  ID                 ID      #REQUIRED
  AuthenticationId   CDATA   #REQUIRED
  ContentSoftwareId  CDATA   #IMPLIED >
 <!-- AUTHENTICATION RESPONSE COMPONENT -->
 <!ELEMENT AuthResp (PackagedContent*) >
 <!ATTLIST AuthResp
  ID                 ID      #REQUIRED
  AuthenticationId   CDATA   #REQUIRED
  SelectedAlgorithmRef NMTOKEN #REQUIRED
  ContentSoftwareId  CDATA   #IMPLIED >
 <!-- TRADING ROLE INFO REQUEST COMPONENT -->
 <!ELEMENT TradingRoleInfoReq EMPTY>
 <!ATTLIST TradingRoleInfoReq
  ID                 ID      #REQUIRED
  TradingRoleList    NMTOKENS #REQUIRED >
 <!-- ORDER COMPONENT -->
 <!ELEMENT Order (PackagedContent*) >
 <!ATTLIST Order
  ID                 ID      #REQUIRED

Burdett Informational [Page 266] RFC 2801 IOTP/1.0 April 2000

  xml:lang           NMTOKEN #REQUIRED
  OrderIdentifier    CDATA   #REQUIRED
  ShortDesc          CDATA   #REQUIRED
  OkFrom             CDATA   #REQUIRED
  OkTo               CDATA   #REQUIRED
  ApplicableLaw      CDATA   #REQUIRED
  ContentSoftwareId  CDATA   #IMPLIED >
 <!-- ORGANISATION COMPONENT -->
 <!ELEMENT Org (TradingRole+, ContactInfo?,
      PersonName?, PostalAddress?)>
 <!ATTLIST Org
  ID                 ID      #REQUIRED
  xml:lang           NMTOKEN #REQUIRED
  OrgId              CDATA   #REQUIRED
  LegalName          CDATA   #IMPLIED
  ShortDesc          CDATA   #IMPLIED
  LogoNetLocn        CDATA   #IMPLIED >
 <!ELEMENT TradingRole EMPTY >
 <!ATTLIST TradingRole
  ID      ID#REQUIRED
  TradingRole        NMTOKEN #REQUIRED
  IotpMsgIdPrefix    NMTOKEN #REQUIRED
  CancelNetLocn      CDATA   #IMPLIED
  ErrorNetLocn       CDATA   #IMPLIED
  ErrorLogNetLocn  CDATA           #IMPLIED >
 <!ELEMENT ContactInfo EMPTY >
 <!ATTLIST ContactInfo
  xml:lang           NMTOKEN #IMPLIED
  Tel                CDATA   #IMPLIED
  Fax                CDATA   #IMPLIED
  Email              CDATA   #IMPLIED
  NetLocn            CDATA   #IMPLIED >
 <!ELEMENT PersonName EMPTY >
 <!ATTLIST PersonName
  xml:lang           NMTOKEN #IMPLIED
  Title              CDATA   #IMPLIED
  GivenName          CDATA   #IMPLIED
  Initials           CDATA   #IMPLIED
  FamilyName         CDATA   #IMPLIED >

Burdett Informational [Page 267] RFC 2801 IOTP/1.0 April 2000

 <!ELEMENT PostalAddress EMPTY >
 <!ATTLIST PostalAddress
  xml:lang           NMTOKEN #IMPLIED
  AddressLine1       CDATA   #IMPLIED
  AddressLine2       CDATA   #IMPLIED
  CityOrTown         CDATA   #IMPLIED
  StateOrRegion      CDATA   #IMPLIED
  PostalCode         CDATA   #IMPLIED
  Country            CDATA   #IMPLIED
  LegalLocation (True | False) 'False' >
 <!-- BRAND LIST COMPONENT -->
 <!ELEMENT BrandList (Brand+, ProtocolAmount+,
  CurrencyAmount+, PayProtocol+) >
 <!ATTLIST BrandList
  ID                 ID      #REQUIRED
  xml:lang           NMTOKEN #REQUIRED
  ShortDesc          CDATA   #REQUIRED
  PayDirection (Debit | Credit) #REQUIRED >
 <!ELEMENT Brand (ProtocolBrand*, PackagedContent*) >
 <!ATTLIST Brand
  ID                 ID      #REQUIRED
  xml:lang           NMTOKEN #IMPLIED
  BrandId            CDATA   #REQUIRED
  BrandName          CDATA   #REQUIRED
  BrandLogoNetLocn   CDATA   #REQUIRED
  BrandNarrative     CDATA   #IMPLIED
  ProtocolAmountRefs IDREFS  #REQUIRED
  ContentSoftwareId  CDATA   #IMPLIED >
 <!ELEMENT ProtocolBrand (PackagedContent*) >
 <!ATTLIST ProtocolBrand
  ProtocolId         CDATA   #REQUIRED
  ProtocolBrandId    CDATA   #REQUIRED >
 <!ELEMENT ProtocolAmount (PackagedContent*) >
 <!ATTLIST ProtocolAmount
  ID                 ID      #REQUIRED
  PayProtocolRef     IDREF   #REQUIRED
  CurrencyAmountRefs IDREFS  #REQUIRED
  ContentSoftwareId  CDATA   #IMPLIED >
 <!ELEMENT CurrencyAmount EMPTY >
 <!ATTLIST CurrencyAmount
  ID                 ID      #REQUIRED
  Amount             CDATA   #REQUIRED

Burdett Informational [Page 268] RFC 2801 IOTP/1.0 April 2000

  CurrCodeType       NMTOKEN 'ISO4217-A'
  CurrCode           CDATA   #REQUIRED >
 <!ELEMENT PayProtocol (PackagedContent*) >
 <!ATTLIST PayProtocol
  ID                 ID      #REQUIRED
  xml:lang           NMTOKEN #IMPLIED
  ProtocolId         NMTOKEN #REQUIRED
  ProtocolName       CDATA   #REQUIRED
  ActionOrgRef       NMTOKEN #REQUIRED
  PayReqNetLocn      CDATA   #IMPLIED
  SecPayReqNetLocn   CDATA   #IMPLIED
  ContentSoftwareId  CDATA   #IMPLIED >
 <!-- BRAND SELECTION COMPONENT -->
 <!ELEMENT BrandSelection (BrandSelBrandInfo?,
      BrandSelProtocolAmountInfo?,
      BrandSelCurrencyAmountInfo?) >
 <!ATTLIST BrandSelection
  ID                 ID      #REQUIRED
  BrandListRef       NMTOKEN #REQUIRED
  BrandRef           NMTOKEN #REQUIRED
  ProtocolAmountRef  NMTOKEN #REQUIRED
  CurrencyAmountRef  NMTOKEN #REQUIRED >
 <!ELEMENT BrandSelBrandInfo (PackagedContent+) >
 <!ATTLIST BrandSelBrandInfo
  ID                 ID      #REQUIRED
  ContentSoftwareId  CDATA   #IMPLIED >
 <!ELEMENT BrandSelProtocolAmountInfo (PackagedContent+) >
 <!ATTLIST BrandSelProtocolAmountInfo
  ID                 ID      #REQUIRED
  ContentSoftwareId  CDATA   #IMPLIED >
 <!ELEMENT BrandSelCurrencyAmountInfo (PackagedContent+) >
 <!ATTLIST BrandSelCurrencyAmountInfo
  ID                 ID      #REQUIRED
  ContentSoftwareId  CDATA   #IMPLIED >
 <!-- PAYMENT COMPONENT -->
 <!ELEMENT Payment EMPTY >
 <!ATTLIST Payment
  ID                 ID      #REQUIRED
  OkFrom             CDATA   #REQUIRED
  OkTo               CDATA   #REQUIRED
  BrandListRef       NMTOKEN #REQUIRED

Burdett Informational [Page 269] RFC 2801 IOTP/1.0 April 2000

  SignedPayReceipt (True | False) #REQUIRED
  StartAfterRefs     NMTOKENS #IMPLIED >
 <!-- PAYMENT SCHEME COMPONENT -->
 <!ELEMENT PaySchemeData (PackagedContent+) >
 <!ATTLIST PaySchemeData
  ID                 ID      #REQUIRED
  PaymentRef         NMTOKEN #IMPLIED
  ConsumerPaymentId  CDATA   #IMPLIED
  PaymentHandlerPayId CDATA  #IMPLIED
  ContentSoftwareId  CDATA   #IMPLIED >
 <!-- PAYMENT RECEIPT COMPONENT -->
 <!ELEMENT PayReceipt (PackagedContent*) >
 <!ATTLIST PayReceipt
  ID                 ID      #REQUIRED
  PaymentRef         NMTOKEN #REQUIRED
  PayReceiptNameRefs NMTOKENS #IMPLIED
  ContentSoftwareId  CDATA   #IMPLIED >
 <!-- PAYMENT NOTE COMPONENT -->
 <!ELEMENT PaymentNote (PackagedContent+) >
 <!ATTLIST PaymentNote
   ID                ID      #REQUIRED
   ContentSoftwareId CDATA   #IMPLIED >
 <!-- DELIVERY COMPONENT -->
 <!ELEMENT Delivery (DeliveryData?, PackagedContent*) >
 <!ATTLIST Delivery
  ID                 ID      #REQUIRED
  xml:lang           NMTOKEN #REQUIRED
  DelivExch          (True | False) #REQUIRED
  DelivAndPayResp    (True | False) #REQUIRED
  ActionOrgRef       NMTOKEN #IMPLIED >
 <!ELEMENT DeliveryData (PackagedContent*) >
 <!ATTLIST DeliveryData
  xml:lang           NMTOKEN #IMPLIED
  OkFrom             CDATA   #REQUIRED
  OkTo               CDATA   #REQUIRED
  DelivMethod        NMTOKEN #REQUIRED
  DelivToRef         NMTOKEN #REQUIRED
  DelivReqNetLocn    CDATA   #IMPLIED
  SecDelivReqNetLocn CDATA   #IMPLIED

Burdett Informational [Page 270] RFC 2801 IOTP/1.0 April 2000

  ContentSoftwareId  CDATA   #IMPLIED >
 <!-- CONSUMER DELIVERY DATA COMPONENT -->
 <!ELEMENT ConsumerDeliveryData EMPTY >
 <!ATTLIST ConsumerDeliveryData
  ID                 ID      #REQUIRED
  ConsumerDeliveryId CDATA   #REQUIRED >
 <!-- DELIVERY NOTE COMPONENT -->
 <!ELEMENT DeliveryNote (PackagedContent+) >
 <!ATTLIST DeliveryNote
  ID                 ID      #REQUIRED
  xml:lang           NMTOKEN #REQUIRED
  DelivHandlerDelivId CDATA  #IMPLIED
  ContentSoftwareId  CDATA   #IMPLIED >
 <!-- STATUS COMPONENT -->
 <!ELEMENT Status EMPTY >
 <!ATTLIST Status
  ID                 ID      #REQUIRED
  xml:lang           NMTOKEN #REQUIRED
  StatusType         NMTOKEN #REQUIRED
  ElRef              NMTOKEN #IMPLIED
  ProcessState (NotYetStarted | InProgress |
      CompletedOk | Failed | ProcessError) #REQUIRED
  CompletionCode     NMTOKEN #IMPLIED
  ProcessReference   CDATA   #IMPLIED
  StatusDesc         CDATA   #IMPLIED >
 <!-- TRADING ROLE DATA COMPONENT -->
 <!ELEMENT TradingRoleData (PackagedContent+) >
 <!ATTLIST TradingRoleData
   ID                ID      #REQUIRED
   OriginatorElRef   NMTOKEN #REQUIRED
   DestinationElRefs NMTOKENS #REQUIRED >
 <!-- INQUIRY TYPE COMPONENT -->
 <!ELEMENT InquiryType EMPTY >
 <!ATTLIST InquiryType
  ID                 ID      #REQUIRED
  Type               NMTOKEN #REQUIRED
  ElRef              NMTOKEN #IMPLIED
  ProcessReference   CDATA   #IMPLIED >

Burdett Informational [Page 271] RFC 2801 IOTP/1.0 April 2000

 <!-- ERROR COMPONENT -->
 <!ELEMENT ErrorComp (ErrorLocation+, PackagedContent*) >
 <!ATTLIST ErrorComp
  ID                 NMTOKEN #REQUIRED
  xml:lang           NMTOKEN #REQUIRED
  ErrorCode          NMTOKEN #REQUIRED
  ErrorDesc          CDATA   #REQUIRED
  Severity (Warning|TransientError|HardError) #REQUIRED
  MinRetrySecs       CDATA   #IMPLIED
  SwVendorErrorRef   CDATA   #IMPLIED >
 <!ELEMENT ErrorLocation EMPTY >
 <!ATTLIST ErrorLocation
  ElementType        NMTOKEN #REQUIRED
  IotpMsgRef         NMTOKEN #IMPLIED
  BlkRef             NMTOKEN #IMPLIED
  CompRef            NMTOKEN #IMPLIED
  ElementRef         NMTOKEN #IMPLIED
  AttName            NMTOKEN #IMPLIED >
 <!--
 ******************************************************
 * TRADING BLOCKS                                     *
 ******************************************************
  -->
 <!-- TRADING PROTOCOL OPTIONS BLOCK -->
 <!ELEMENT TpoBlk ( ProtocolOptions, BrandList*, Org* ) >
 <!ATTLIST TpoBlk
  ID                 ID      #REQUIRED >
 <!-- TPO SELECTION BLOCK -->
 <!ELEMENT TpoSelectionBlk (BrandSelection+) >
 <!ATTLIST TpoSelectionBlk
  ID                 ID      #REQUIRED >
 <!-- OFFER RESPONSE BLOCK -->
 <!ELEMENT OfferRespBlk (Status, Order?, Payment*,
              Delivery?, TradingRoleData*) >
 <!ATTLIST OfferRespBlk
  ID                 ID      #REQUIRED >

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 <!-- AUTHENTICATION REQUEST BLOCK -->
 <!ELEMENT AuthReqBlk (AuthReq*, TradingRoleInfoReq?) >
 <!ATTLIST AuthReqBlk
  ID                 ID      #REQUIRED >
 <!-- AUTHENTICATION RESPONSE BLOCK -->
 <!ELEMENT AuthRespBlk (AuthResp?, Org*) >
 <!ATTLIST AuthRespBlk
  ID                 ID      #REQUIRED >
 <!-- AUTHENTICATION STATUS BLOCK -->
 <!ELEMENT AuthStatusBlk (Status) >
 <!ATTLIST AuthStatusBlk
  ID                 ID      #REQUIRED >
 <!-- PAYMENT REQUEST BLOCK -->
 <!ELEMENT PayReqBlk (Status+, BrandList, BrandSelection,
      Payment, PaySchemeData?, Org*, TradingRoleData*) >
 <!ATTLIST PayReqBlk
  ID                 ID      #REQUIRED >
 <!-- PAYMENT EXCHANGE BLOCK -->
 <!ELEMENT PayExchBlk (PaySchemeData) >
 <!ATTLIST PayExchBlk
  ID                 ID      #REQUIRED >
 <!-- PAYMENT RESPONSE BLOCK -->
 <!ELEMENT PayRespBlk (Status, PayReceipt?, PaySchemeData?,
      PaymentNote?, TradingRoleData*) >
 <!ATTLIST PayRespBlk
  ID                 ID      #REQUIRED >
 <!-- DELIVERY REQUEST BLOCK -->
 <!ELEMENT DeliveryReqBlk (Status+, Order, Org*, Delivery,
      ConsumerDeliveryData?, TradingRoleData*) >
 <!ATTLIST DeliveryReqBlk
  ID                 ID      #REQUIRED >
 <!-- DELIVERY RESPONSE BLOCK -->
 <!ELEMENT DeliveryRespBlk (Status, DeliveryNote) >
 <!ATTLIST DeliveryRespBlk
  ID                 ID      #REQUIRED >

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 <!-- INQUIRY REQUEST BLOCK -->
 <!ELEMENT InquiryReqBlk ( InquiryType, PaySchemeData? ) >
 <!ATTLIST InquiryReqBlk
  ID                 ID      #REQUIRED >
 <!-- INQUIRY RESPONSE BLOCK -->
 <!ELEMENT InquiryRespBlk (Status, PaySchemeData?) >
 <!ATTLIST InquiryRespBlk
  ID                 ID      #REQUIRED
  LastReceivedIotpMsgRef NMTOKEN #IMPLIED
  LastSentIotpMsgRef NMTOKEN #IMPLIED >
 <!-- PING REQUEST BLOCK -->
 <!ELEMENT PingReqBlk (Org*)>
 <!ATTLIST PingReqBlk
  ID                 ID      #REQUIRED>
 <!-- PING RESPONSE BLOCK -->
 <!ELEMENT PingRespBlk (Org+)>
 <!ATTLIST PingRespBlk
  ID                 ID      #REQUIRED
  PingStatusCode (Ok | Busy | Down) #REQUIRED
  SigVerifyStatusCode (Ok | NotSupported | Fail) #IMPLIED
  xml:lang           NMTOKEN #IMPLIED
  PingStatusDesc     CDATA   #IMPLIED>
 <!-- ERROR BLOCK -->
 <!ELEMENT ErrorBlk (ErrorComp+, PaySchemeData*) >
 <!ATTLIST ErrorBlk
  ID                 ID      #REQUIRED >
 <!-- CANCEL BLOCK -->
 <!ELEMENT CancelBlk (Status) >
 <!ATTLIST CancelBlk
  ID                 ID      #REQUIRED >
 <!--
 ******************************************************
 * IOTP SIGNATURES BLOCK DEFINITION                   *
 ******************************************************
 -->

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 <!ELEMENT IotpSignatures (Signature+ ,Certificate*) >
 <!ATTLIST IotpSignatures
     ID        ID        #IMPLIED
 >
 <!--
 ******************************************************
 * IOTP SIGNATURE COMPONENT DEFINITION                *
 ******************************************************
 -->
 <!ELEMENT Signature (Manifest, Value+) >
 <!ATTLIST Signature
     ID         ID        #IMPLIED
 >
 <!ELEMENT Manifest
     (       Algorithm+,
             Digest+,
             Attribute*,
             OriginatorInfo,
             RecipientInfo+
     )
 >
 <!ATTLIST Manifest
     LocatorHRefBase       CDATA             #IMPLIED
 >
 <!ELEMENT Algorithm (Parameter*) >
 <!ATTLIST Algorithm
     ID                     ID                #REQUIRED
     type            (digest|signature)      #IMPLIED
     name                  NMTOKEN           #REQUIRED
 >
 <!ELEMENT Digest (Locator, Value) >
 <!ATTLIST Digest
     DigestAlgorithmRef    IDREF             #REQUIRED
 >
 <!ELEMENT Attribute ( ANY ) >
 <!ATTLIST Attribute
     type                   NMTOKEN           #REQUIRED
     critical            ( true | false )     #REQUIRED
 >
 <!ELEMENT OriginatorInfo ANY >

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 <!ATTLIST OriginatorInfo
     OriginatorRef           NMTOKEN          #IMPLIED
 >
 <!ELEMENT RecipientInfo ANY >
 <!ATTLIST RecipientInfo
     SignatureAlgorithmRef   IDREF            #REQUIRED
     SignatureValueRef       IDREF            #IMPLIED
     SignatureCertRef        IDREF            #IMPLIED
     RecipientRefs           NMTOKENS         #IMPLIED
 >
 <!ELEMENT KeyIdentifier EMPTY>
 <!ATTLIST KeyIdentifier
     value                    CDATA           #REQUIRED
 >
 <!ELEMENT Parameter ANY >
 <!ATTLIST Parameter
     type                     CDATA           #REQUIRED
 >
 <!--
 ******************************************************
 * IOTP CERTIFICATE COMPONENT DEFINITION              *
 ******************************************************
 -->
 <!ELEMENT Certificate
  (  IssuerAndSerialNumber,  ( Value | Locator ) )
 >
 <!ATTLIST Certificate
     ID                        ID                #IMPLIED
     type                      NMTOKEN           #REQUIRED
 >
 <!ELEMENT IssuerAndSerialNumber EMPTY >
 <!ATTLIST IssuerAndSerialNumber
     issuer                     CDATA            #REQUIRED
     number                     CDATA            #REQUIRED
 >
 <!--
 ******************************************************
 * IOTP SHARED COMPONENT DEFINITION                   *
 ******************************************************

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<!ELEMENT Value ( #PCDATA ) >

 <!ATTLIST Value
     ID               ID           #IMPLIED
     encoding    (base64|none)    'base64'
 >
 <!ELEMENT Locator EMPTY>
 <!ATTLIST Locator
     xml:link        CDATA         #FIXED        'simple'
     href            CDATA         #REQUIRED
 >

14. Glossary

 This section contains a glossary of some of the terms used within
 this specification in alphabetical order.
        NAME                            DESCRIPTION
 Authenticator      The Organisation which is requesting the
                    authentication of another Organisation, and
 Authenticatee      The Organisation being authenticated by an
                    Authenticator
 Business Error     See Status Component.
 Brand              A Brand is the mark which identifies a particular
                    type of Payment Instrument. A list of Brands are
                    the payment options which are presented by the
                    Merchant to the Consumer and from which the
                    Consumer makes a selection. Each Brand may have a
                    different Payment Handler. Examples of Brands
                    include:
                     o payment association and proprietary Brands,
                       for example MasterCard, Visa, American Express,
                       Diners Club, American Express, Mondex,
                       GeldKarte, CyberCash, etc.
                     o Promotional Brands (see below). These include:
                     o store Brands, where the Payment Instrument is
                       issued to a Consumer by a particular Merchant,
                       for example Walmart, Sears, or Marks and
                       Spencer (UK)
                     o coBrands, for example American Advantage Visa,
                       where an a company uses their own Brand in
                       conjunction with, typically, a payment
                       association Brand.

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 Consumer           The Organisation which is to receive the benefit
                    of and typically pay for the goods or services.
 ContentSoftwareId  This contains information which identifies the
                    software which generated the content of the
                    element. Its purpose is to help resolve
                    interoperability problems that might occur as a
                    result of incompatibilities between messages
                    produced by different software. It is a single
                    text string in the language defined by xml:lang.
                    It must contain, as a minimum:
                     o the name of the software manufacturer
                     o the name of the software
                     o the version of the software, and
                     o the build of the software
                    It is recommended that this attribute is included
                    whenever the software which generated the content
                    cannot be identified from the SoftwareId attribute
                    on the Message Id Component (see section 3.3.2)
 Customer Care      An Organisation that is providing customer care
 Provider           typically on behalf of a Merchant. Examples of
                    customer care include, responding to problems
                    raised by a Consumer arising from an IOTP
                    Transaction that the Consumer took part in.
 Delivery Handler   The Organisation that directly delivers the goods
                    or services to the Consumer on behalf of the
                    Merchant. Delivery can be in the form of either
                    digital goods (e.g., a [MIME] message), or
                    physically delivered using the post or a courier.
 Document Exchange  A Document Exchange consists of a set of IOTP
                    Messages exchanged between two parties that
                    implement part or all of two Trading Exchanges
                    simultaneously in order to minimise the number of
                    actual IOTP Messages which must be sent over the
                    Internet.
                    Document Exchanges are combined together in
                    sequence to implement a particular IOTP
                    Transaction.
 Dual Brand         A Dual Brand means that a single Payment
                    Instrument may be used as if it were two separate
                    Brands. For example there could be a single
                    Japanese "UC" MasterCard which can be used as

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                    either a UC card or a regular MasterCard. The UC
                    card Brand and the MasterCard Brand could each
                    have their own separate Payment Handlers. This
                    means that:
                     o the Merchant treats, for example "UC" and
                       "MasterCard" as two separate Brands when
                       offering a list of Brands to the Consumer,
                     o the Consumer chooses a Brand, for example
                       either "UC" or "MasterCard,
                     o the Consumer IOTP aware application determines
                       which Payment Instrument(s) match the chosen
                       Brand, and selects, perhaps with user
                       assistance, the correct Payment Instrument to
                       use.
 Error Block        An Error Block reports that a Technical Error was
                    found in an IOTP Message that was previously
                    received. Typically Technical Errors are caused by
                    errors in the XML which has been received or some
                    technical failure of the processing of the IOTP
                    Message. Frequently the generation or receipt of
                    an Error Block will result in failure of the IOTP
                    Transaction. They are distinct from Business
                    Errors, reported in a Status Component, which can
                    also cause failure of an IOTP Transaction.
 Exchange Block     An Exchange Block is sent between the two Trading
                    Roles involved in a Trading Exchange. It contains
                    one or more Trading Components. Exchange Blocks
                    are always sent after a Request Block and before a
                    Response Block in a Trading Exchange. The content
                    of an Exchange Block is dependent on the type of
                    Trading Exchange being carried out.
 IOTP Message       An IOTP Message is the outermost wrapper for the
                    document(s) which are sent between Trading Roles
                    that are taking part in a trade. It is a well
                    formed XML document. The documents it contains
                    consist of:
                     o a Transaction Reference Block to uniquely
                       identify the IOTP Transaction of which the IOTP
                       Message is part,
                     o an optional Signature Block to digitally sign
                       the Trading Blocks or Trading Components
                       associated with the IOTP Transaction
                     o an optional Error Block to report on technical
                       errors contained in a previously received IOTP
                       Message, and

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                     o a collection of IOTP Trading Blocks which
                       carries the data required to carry out an IOTP
                       Transaction.
 IOTP Transaction   An instance of an Internet Open Trading Protocol
                    Transaction consists of a set of IOTP Messages
                    transferred between Trading Roles. The rules for
                    what may be contained in the IOTP Messages is
                    defined by the Transaction Type of the IOTP
                    Transaction.
 IOTP Transaction   A Transaction Type identifies the type an of IOTP
 Type               Transaction. Examples of Transaction Type include:
                    Purchase, Refund, Authentication, Withdrawal,
                    Deposit (of electronic cash). The Transaction Type
                    specifies for an IOTP Transaction:
                     o the Trading Exchanges which may be included in
                       the transaction,
                     o how those Trading Exchanges may be combined to
                       meet the business needs of the transaction
                     o which Trading Blocks may be included in the
                       IOTP Messages that make up the transaction
                     o Consult this specification for the rules that
                       apply for each Transaction Type.
 Merchant           The Organisation from whom the service or goods
                    are being obtained, who is legally responsible for
                    providing the goods or services and receives the
                    benefit of any payment made
 Merchant Customer  The Organisation that is involved with customer
 Care Provider      dispute negotiation and resolution on behalf of
                    the Merchant
 Organisation       A company or individual that takes part in a Trade
                    as a Trading Role. The Organisations may take one
                    or more of the roles involved in the Trade
 Payment Handler    The Organisation that physically receives the
                    payment from the Consumer on behalf of the
                    Merchant
 Payment            A Payment Instrument is the means by which
 Instrument         Consumer pays for goods or services offered by a
                    Merchant. It can be, for example:
                     o a credit card such as MasterCard or Visa;
                     o a debit card such as MasterCard's Maestro;
                     o a smart card based electronic cash Payment

Burdett Informational [Page 280] RFC 2801 IOTP/1.0 April 2000

                       Instrument such as a Mondex Card, a GeldKarte
                       card or a Visa Cash card
                     o a software based electronic payment account
                       such as a CyberCash's CyberCoin or DigiCash
                       account.
                    All Payment Instruments have a number, typically
                    an account number, by which the Payment Instrument
                    can be identified.
 Promotional Brand  A Promotional Brand means that, if the Consumer
                    pays with that Brand, then the Consumer will
                    receive some additional benefit which can be
                    received in two ways:
                     o at the time of purchase. For example if a
                       Consumer pays with a "Walmart MasterCard" at a
                       Walmart web site, then a 5% discount might
                       apply, which means the Consumer actually pays
                       less,
                     o from their Payment Instrument (card) issuer
                       when the payment appears on their statement.
                       For example loyalty points in a frequent flyer
                       scheme could be awarded based on the total
                       payments made with the Payment Instrument since
                       the last statement was issued.
                    Each Promotional Brand should be identified as a
                    separate Brand in the list of Brands offered by
                    the Merchant.
 Receipt Component  A Receipt Component is a record of the successful
                    completion of a Trading Exchange. Examples of
                    Receipt Components include: Payment Receipts, and
                    Delivery Notes. It's content may dependent on the
                    technology used to perform the Trading Exchange.
                    For example a Secure Electronic Transaction (SET)
                    payment receipt consists of SET payment messages
                    which record the result of the payment.
 Request Block      A Request Block is Trading Block that contains a
                    request for a Trading Exchange to start. The
                    Trading Components in a Request Block may be
                    signed by a Signature Block so that their
                    authenticity may be checked and to determine that
                    the Trading Exchange being requested is
                    authorised. Authorisation for a Trading Exchange
                    to start can be provided by the signatures
                    contained on Receipt Components contained in

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                    Response Blocks resulting from previously
                    completed Trading Exchanges.  Examples of Request
                    Blocks are Payment Request and Delivery Request
 Response Block     A Response Block is a Trading Block that indicates
                    that a Trading Exchange is complete. It is sent by
                    the Trading Role that received a Request Block to
                    the Trading Role that sent the Request Block. The
                    Response Block contains a Status Component that
                    contains information about the completion of the
                    Trading Exchange, for example it indicates whether
                    or not the Trading Exchange completed
                    successfully. For some Trading Exchanges the
                    Response Block contains a Receipt Component that
                    forms a record of the Trading Exchange. Receipt
                    Components may be digitally signed using a
                    Signature Block to make completion non-refutable.
                    Examples of Response Blocks include Offer
                    Response, Payment Response and Delivery Response.
 Signature Block    A Signature Block is a Trading Block that contains
                    one or more digital signatures in the form of
                    Signature Components. A Signature Component may
                    digitally sign any Block or Component in any IOTP
                    Message in the same IOTP Transaction.
 Status Component   A Status Component contains information that
                    describes the state of a Trading Exchange.
                    Before the Trading Exchange is complete the Status
                    Component can indicate information about how the
                    Trading Exchange is progressing.
                    Once a Trading Exchange is complete the Status
                    Component can only indicate the success of the
                    Trading Exchange or that a Business Error has
                    occurred.
                    A Business Error indicates that continuation with
                    the Trading Exchange was not possible because of
                    some business rule or logic, for example,
                    "insufficient funds available", rather than any
                    Technical Error associated with the content or
                    format of the IOTP Messages in the IOTP
                    Transaction.
 Technical Error    See Error Block.

Burdett Informational [Page 282] RFC 2801 IOTP/1.0 April 2000

 Trading Block      A Trading Block consists of one or more Trading
                    Components. One or more Trading Blocks may be
                    contained within the IOTP Messages which are
                    physically sent in the form of [XML] documents
                    between the different Trading Roles that are
                    taking part in a trade. Trading Blocks are of
                    three main types:
                     o a Request Block,
                     o an Exchange Block, or a
                     o a Response Block
 Trading Component  A Trading Component is a collection of XML
                    elements and attributes. Trading Components are
                    the child elements of the Trading Blocks. Examples
                    of Trading Components are: Offer, Brand List,
                    Payment Receipt, Delivery [information], Payment
                    Amount [information]
 Trading Exchange   A Trading Exchange consists of the exchange,
                    between two Trading Roles, of a sequence of
                    documents. The documents may be in the form of
                    Trading Blocks or they may be transferred by some
                    other means, for example through entering data
                    into a web page. Each Trading Exchange consists of
                    three main parts:
                     o the sending of a Request Block by one Trading
                       Role (the initiator) to another Trading Role
                       (the recipient),
                     o the optional exchange of one or more Exchange
                       Blocks between the recipient and the initiator,
                       until eventually,
                     o the Trading Role that received the Request
                       Block sends a Response Block to the initiator.
                    A Trading Exchange is designed to implement a
                    useful service of some kind. Examples of Trading
                    Exchanges/services are:
                     o Offer, which results in a Consumer receiving
                       an offer from a Merchant to carry out a
                       business transaction of some kind,
                     o Payment, where a Consumer makes a payment to a
                       Payment Handler,
                     o Delivery, where a Consumer requests, and
                       optionally obtains, delivery of goods or
                       services from a Delivery Handler, and
                     o Authentication, where any Trading Role may
                       request and receive information about another
                       Trading Role.

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 Trading Role       A Trading Role identifies the different ways in
                    which Organisations can participate in a trade.
                    There are five Trading Roles: Consumer, Merchant,
                    Payment Handler, Delivery Handler, and Merchant
                    Customer Care Provider.
 Transaction        A Transaction Reference Block identifies an IOTP
 Reference Block    Transaction. It contains data that identifies:
                     o the Transaction Type,
                     o the IOTP Transaction uniquely, through a
                       globally unique transaction identifier
                     o the IOTP Message uniquely within the IOTP
                       Transaction, through a message identifier
                    The Transaction Reference Block may also contain
                    references to other transactions which may or may
                    not be IOTP Transactions

15. References

 This section contains references to related documents identified in
 this specification.
 [Base64]    Freed, N. and N. Borenstein, "Multipurpose Internet Mail
             Extensions (MIME) Part One: Format of Internet Message
             Bodies", RFC 2045, November 1996.
 [DOM-HASH]  Maruyama, H., Tamura, K. and N. Uramoto, "Digest Values
             for DOM (DOMHASH)", RFC 2803, April 2000.
 [DNS]       Mockapetris, P., "Domain names - concepts and
             facilities", STD 13, RFC 1034, November 1987.
 [DNS]       Mockapetris, P., "Domain names - implementation and
             specification", STD 13, RFC 1035, November 1987.
 [DSA]       The Digital Signature Algorithm (DSA) published by the
             National Institute of Standards and Technology (NIST) in
             the Digital Signature Standard (DSS), which is a part of
             the US government's Capstone project.
 [ECCDSA]    Elliptic Curve Cryptosystems Digital Signature Algorithm
             (ECCDSA). Elliptic curve cryptosystems are analogues of
             public-key cryptosystems such as RSA in which modular
             multiplication is replaced by the elliptic curve addition
             operation. See: V. S. Miller. Use of elliptic curves in
             cryptography. In Advances in Cryptology - Crypto '85,
             pages 417-426, Springer-Verlag, 1986.

Burdett Informational [Page 284] RFC 2801 IOTP/1.0 April 2000

 [HMAC]      Krawczyk, H., Bellare, M. and R. Canetti, "HMAC:  Keyed-
             Hashing for Message Authentication", RFC 2104, February
             1997.
 [HTML]      Berners-Lee, T. and D. Connolly, "Hypertext Markup
             Language - 2.0", RFC 1866, November 1995.
 [HTML]      Hyper Text Mark Up Language. The Hypertext Mark-up
             Language (HTML) is a simple mark-up language used to
             create hypertext documents that are platform independent.
             See the World Wide Web (W3C) consortium web site at:
             http://www.w3.org/MarkUp/
 [HTTP]      Berners-Lee, T., Fielding, R. and H. Frystyk, "Hypertext
             Transfer Protocol -- HTTP/1.0", RFC 1945, May 1996.
 [HTTP]      Fielding, R., Gettys, J., Mogul, J., Frystyk, T. and T.
             Berners-Lee, "Hypertext Transfer Protocol -- HTTP/1.1.",
             RFC 2616, June 1999.
 [IANA]      The Internet Assigned Numbers Authority. The organisation
             responsible for co-ordinating the names and numbers
             associated with the Internet. See http://www.iana.org/
 [ISO4217]   ISO 4217: Codes for the Representation of Currencies.
             Available from ANSI or ISO.
 [IOTPDSIG]  Davidson, K. and Y. Kawatsura, "Digital Signatures for
             the v1.0 Internet Open Trading Protocol (IOTP)", RFC
             2802, April 2000.
 [MD5]       Rivest, R., "The MD5 Message-Digest Algorithm", RFC 1321,
             April 1992.
 [MIME]      Crocker, D., "Standard for the Format of ARPA Internet
             Text Messages", STD 11, RFC 822, August 1982.
 [MIME]      Freed, N. and N. Borenstein, "Multipurpose Internet Mail
             Extensions (MIME) Part One: Format of Internet Message
             Bodies", RFC 2045, November 1996.
 [MIME]      Freed, N. and N. Borenstein, "Multipurpose Internet Mail
             Extensions (MIME) Part Two: Media Types", RFC 2046,
             November 1996.
 [MIME]      Moore, K., "MIME (Multipurpose Internet Mail Extensions)
             Part Three: Message Header Extensions for Non-ASCII Text"
             RFC 2047, November 1996.

Burdett Informational [Page 285] RFC 2801 IOTP/1.0 April 2000

 [MIME]      Freed, N., Klensin, J. and J. Postel, "Multipurpose
             Internet Mail Extensions (MIME) Part Four: Registration
             Procedures", RFC 2048, November 1996.
 [MIME]      Freed, N. and N. Borenstein, "Multipurpose Internet Mail
             Extensions (MIME) Part Five: Conformance Criteria and
             Examples" RFC 2049, November 1996.
 [OPS]       Open Profiling Standard. A proposed standard which
             provides a framework with built-in privacy safeguards for
             the trusted exchange of profile information between
             individuals and web sites.  Being developed by Netscape
             and Microsoft amongst others.
 [RFC1738]   Berners-Lee, T., Masinter, L. and M. McCahill, "Uniform
             Resource Locators (URL)", RFC 1738, December 1994.
 [RFC2434]   Narten, T. and H. Alvestrand, "Guidelines for Writing an
             IANA Considerations Section in RFCs", BCP 26, RFC 2434,
             October 1998.
 [RSA]       RSA is a public-key cryptosystem for both encryption and
             authentication supported by RSA Data Security Inc. See:
             R. L. Rivest, A. Shamir, and L.M. Adleman. A method for
             obtaining digital signatures and public-key
             cryptosystems. Communications of the ACM, 21(2): 120-126,
             February 1978.
 [SCCD]      Secure Channel Credit Debit. A method of conducting a
             credit or debit card payment where unauthorised access to
             account information is prevented through use of secure
             channel transport mechanisms such as SSL/TLS. An IOTP
             supplement describing how SCCD works is under
             development.
 [SET]       Secure Electronic Transaction Specification, Version 1.0,
             May 31, 1997. Supports credit and debit card payments
             using certificates at the Consumer and Merchant to help
             ensure authenticity.  Download from:
             <http://www.setco.org>.
 [SSL/TLS]   Dierks, T. and C. Allen, "The TLS Protocol Version 1.0",
             RFC 2246, January 1999.
 [SHA1]      [FIPS-180-1]"Secure Hash Standard", National Institute of
             Standards and Technology, US Department Of Commerce,
             April 1995. Also known as: 59 Fed Reg. 35317 (1994). See
             http://www.itl.nist.gov/div897/pubs/fip180-1.htm

Burdett Informational [Page 286] RFC 2801 IOTP/1.0 April 2000

 [UTC]       Universal Time Co-ordinated. A method of defining time
             absolutely relative to Greenwich Mean Time (GMT).
             Typically of the form:  "CCYY-MM-DDTHH:MM:SS.sssZ+n"
             where the "+n" defines the number of hours from GMT. See
             ISO DIS8601.
 [UTF16]     The Unicode Standard, Version 2.0.  The Unicode
             Consortium, Reading, Massachusetts. See ISO/IEC 10646 1
             Proposed Draft Amendment 1
 [X.509]     ITU Recommendation X.509 1993 | ISO/IEC 9594-8: 1995,
             Including Draft Amendment 1: Certificate Extensions
             (Version 3 Certificate)
 [XML        Recommendation for Namespaces in XML, World Wide Web
 Namespace]  Consortium, 14 January 1999, "http://www.w3.org/TR/REC-
             xml-names"
 [XML]       Extensible Mark Up Language. A W3C recommendation. See
             http://www.w3.org/TR/1998/REC-xml-19980210 for the 10
             February 1998 version.

16. Author's Address

 The author of this document is:
 David Burdett
 Commerce One
 4440 Rosewood Drive, Bldg 4
 Pleasanton
 California 94588
 USA
 Phone: +1 (925) 520 4422
 EMail: david.burdett@commerceone.com
 The author of this document particularly wants to thank Mondex
 International Limited (www.mondex.com) for the tremendous support
 provided in the formative stages of the development of this
 specification.

Burdett Informational [Page 287] RFC 2801 IOTP/1.0 April 2000

 In addition the author appreciates the following contributors to this
 protocol (in alphabetic order of company) without which it could not
 have been developed.
  1. Phillip Mullarkey, British Telecom plc
  1. Andrew Marchewka, Canadian Imperial Bank of Commerce
  1. Brian Boesch, CyberCash Inc.
  1. Tom Arnold, CyberSource
  1. Terry Allen, Commerce One (formally Veo Systems)
  1. Richard Brown, GlobeSet Inc.
  1. Peter Chang, Hewlett Packard
  1. Masaaki Hiroya, Hitachi Ltd
  1. Yoshiaki Kawatsura, Hitachi Ltd
  1. Mark Linehan, International Business Machines
  1. Jonathan Sowler, JCP Computer Services Ltd
  1. John Wankmueller, MasterCard International
  1. Steve Fabes, Mondex International Ltd
  1. Donald Eastlake 3rd, Motorola Inc (formerly International

Business Machines Inc)

  1. Surendra Reddy, Oracle Corporation
  1. Akihiro Nakano, Plat Home, Inc. (ex Hitachi Ltd)
  1. Chris Smith, Royal Bank of Canada
  1. Hans Bernhard-Beykirch, SIZ (IT Development and Coordination
       Centre of the German Savings Banks Organisation)
  1. W. Reid Carlisle, Spyrus (ex Citibank Universal Card Services,

formally AT&T Universal Card Services)

  1. Efrem Lipkin, Sun Microsystems

Burdett Informational [Page 288] RFC 2801 IOTP/1.0 April 2000

  1. Tony Lewis, Visa International
 The author would also like to thank the following organisations for
 their support:
  1. Amino Communications
  1. DigiCash
  1. Fujitsu
  1. General Information Systems
  1. Globe Id Software
  1. Hyperion
  1. InterTrader
  1. Nobil I T Corp
  1. Mercantec
  1. Netscape
  1. Nippon Telegraph and Telephone Corporation
  1. Oracle Corporation
  1. Smart Card Integrations Ltd.
  1. Spyrus
  1. Verifone
  1. Unisource nv
  1. Wells Fargo Bank

Burdett Informational [Page 289] RFC 2801 IOTP/1.0 April 2000

17. Full Copyright Statement

 Copyright (C) The Internet Society (2000).  All Rights Reserved.
 This document and translations of it may be copied and furnished to
 others, and derivative works that comment on or otherwise explain it
 or assist in its implementation may be prepared, copied, published
 and distributed, in whole or in part, without restriction of any
 kind, provided that the above copyright notice and this paragraph are
 included on all such copies and derivative works.  However, this
 document itself may not be modified in any way, such as by removing
 the copyright notice or references to the Internet Society or other
 Internet organizations, except as needed for the purpose of
 developing Internet standards in which case the procedures for
 copyrights defined in the Internet Standards process must be
 followed, or as required to translate it into languages other than
 English.
 The limited permissions granted above are perpetual and will not be
 revoked by the Internet Society or its successors or assigns.
 This document and the information contained herein is provided on an
 "AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING
 TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING
 BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION
 HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF
 MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.

Acknowledgement

 Funding for the RFC Editor function is currently provided by the
 Internet Society.

Burdett Informational [Page 290]

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