GENWiki

Premier IT Outsourcing and Support Services within the UK

User Tools

Site Tools


rfc:rfc6137

Independent Submission D. Zisiadis, Ed. Request for Comments: 6137 S. Kopsidas, Ed. Category: Experimental M. Tsavli, Ed. ISSN: 2070-1721 CERTH

                                                      G. Cessieux, Ed.
                                                                  CNRS
                                                         February 2011
           The Network Trouble Ticket Data Model (NTTDM)

Abstract

 Handling multiple sets of network trouble tickets (TTs) originating
 from different participants' inter-connected network environments
 poses a series of challenges for the involved institutions.  A Grid
 is a good example of such a multi-domain project.  Each of the
 participants follows different procedures for handling trouble in its
 domain, according to the local technical and linguistic profile.  The
 TT systems of the participants collect, represent, and disseminate TT
 information in different formats.
 As a result, management of the daily workload by a central Network
 Operation Centre (NOC) is a challenge on its own.  Normalization of
 TTs to a common format at the central NOC can ease presentation,
 storing, and handling of the TTs.  In the present document, we
 provide a model for automating the collection and normalization of
 the TT received by multiple networks forming the Grid.  Each of the
 participants is using its home TT system within its domain for
 handling trouble incidents, whereas the central NOC is gathering the
 tickets in the normalized format for repository and handling.  XML is
 used as the common representation language.  The model was defined
 and used as part of the networking support activity of the EGEE
 (Enabling Grids for E-sciencE) project.

Status of This Memo

 This document is not an Internet Standards Track specification; it is
 published for examination, experimental implementation, and
 evaluation.
 This document defines an Experimental Protocol for the Internet
 community.  This is a contribution to the RFC Series, independently
 of any other RFC stream.  The RFC Editor has chosen to publish this
 document at its discretion and makes no statement about its value for
 implementation or deployment.  Documents approved for publication by
 the RFC Editor are not a candidate for any level of Internet
 Standard; see Section 2 of RFC 5741.

Zisiadis, et al. Experimental [Page 1] RFC 6137 NTTDM February 2011

 Information about the current status of this document, any errata,
 and how to provide feedback on it may be obtained at
 http://www.rfc-editor.org/info/rfc6137.

Copyright Notice

 Copyright (c) 2011 IETF Trust and the persons identified as the
 document authors.  All rights reserved.
 This document is subject to BCP 78 and the IETF Trust's Legal
 Provisions Relating to IETF Documents
 (http://trustee.ietf.org/license-info) in effect on the date of
 publication of this document.  Please review these documents
 carefully, as they describe your rights and restrictions with respect
 to this document.

Table of Contents

 1. Introduction ....................................................4
    1.1. Terminology ................................................5
    1.2. Notations ..................................................6
    1.3. About the Network Trouble Ticket Data Model ................6
    1.4. About the Network Trouble Ticket Implementation ............7
    1.5. Future Plans ...............................................7
 2. NTTDM Types and Definitions .....................................7
    2.1. Types and Definitions for the TYPE Attribute ...............8
         2.1.1. Defined .............................................8
         2.1.2. Free ................................................8
         2.1.3. Multiple ............................................8
         2.1.4. List ................................................8
    2.2. Types and Definitions for the VALID FORMAT Attributes ......9
         2.2.1. Predefined String ...................................9
                2.2.1.1. Definitions of the Predefined Values ......10
         2.2.2. String .............................................13
         2.2.3. Datetime ...........................................13
 3. NTTDM ..........................................................14
    3.1. NTTDM Components ..........................................14
         3.1.1. NTTDM Attributes ...................................14
    3.2. NTTDM Aggregate Classes ...................................15
         3.2.1. NTTDM-Document Class ...............................15
         3.2.2. Ticket Class .......................................15
         3.2.3. Ticket Origin Information ..........................17
                3.2.3.1. PARTNER_ID ................................17
                3.2.3.2. ORIGINAL_ID ...............................17
         3.2.4. Ticket Information .................................17
                3.2.4.1. TT_ID .....................................17
                3.2.4.2. TT_TITLE ..................................18
                3.2.4.3. TT_TYPE ...................................18

Zisiadis, et al. Experimental [Page 2] RFC 6137 NTTDM February 2011

                3.2.4.4. TT_PRIORITY ...............................18
                3.2.4.5. TT_STATUS .................................19
                3.2.4.6. TT_SOURCE .................................19
                3.2.4.7. TT_OPEN_DATETIME ..........................19
                3.2.4.8. TT_CLOSE_DATETIME .........................20
         3.2.5. Trouble Details ....................................20
                3.2.5.1. TT_SHORT_DESCRIPTION ......................20
                3.2.5.2. TT_LONG_DESCRIPTION .......................20
                3.2.5.3. TYPE ......................................21
                3.2.5.4. TT_IMPACT_ASSESSMENT ......................21
                3.2.5.5. START_DATETIME ............................21
                3.2.5.6. DETECT_DATETIME ...........................22
                3.2.5.7. REPORT_DATETIME ...........................22
                3.2.5.8. END_DATETIME ..............................22
                3.2.5.9. TT_LAST_UPDATE_TIME .......................23
                3.2.5.10. TIME_WINDOW_START ........................23
                3.2.5.11. TIME_WINDOW_END ..........................23
                3.2.5.12. WORK_PLAN_START_DATETIME .................24
                3.2.5.13. WORK_PLAN_END_DATETIME ...................24
         3.2.6. Related Data .......................................24
                3.2.6.1. RELATED_EXTERNAL_TICKETS ..................24
                3.2.6.2. ADDITIONAL_DATA ...........................25
                3.2.6.3. RELATED_ACTIVITY ..........................25
                3.2.6.4. HISTORY ...................................25
         3.2.7. Localization and Impact ............................26
                3.2.7.1. AFFECTED_COMMUNITY ........................26
                3.2.7.2. AFFECTED_SERVICE ..........................26
                3.2.7.3. LOCATION ..................................26
                3.2.7.4. NETWORK_NODE ..............................27
                3.2.7.5. NETWORK_LINK_CIRCUIT ......................27
                3.2.7.6. END_LINE_LOCATION_A .......................27
                3.2.7.7. END_LINE_LOCATION_B .......................28
         3.2.8. Contact Information ................................28
                3.2.8.1. OPEN_ENGINEER .............................28
                3.2.8.2. CONTACT_ENGINEERS .........................28
                3.2.8.3. CLOSE_ENGINEER ............................29
         3.2.9. Security ...........................................29
                3.2.9.1. HASH ......................................29
    3.3. NTTDM Representation ......................................29
 4. Internationalization Issues ....................................31
 5. Example ........................................................31
    5.1. Link Failure ..............................................31
 6. Sample Implementation: XML Schema ..............................32
 7. Security Considerations ........................................43
 8. IANA Considerations ............................................44
 9. Contributors ...................................................44
 10. Acknowledgements ..............................................45

Zisiadis, et al. Experimental [Page 3] RFC 6137 NTTDM February 2011

 11. References ....................................................45
    11.1. Normative References .....................................45
    11.2. Informative References ...................................45

1. Introduction

 Problem-impact assessment, reporting, identification, and handling,
 as well as dissemination of trouble information and delegation of
 authority, are some of the main tasks that have to be implemented by
 the members of a Grid in order to successfully manage the network and
 maintain operational efficiency of the services offered to their
 users.
 Different TT systems are used by each network domain, delivering TTs
 in alternate formats, while the TT load is growing proportionally
 with network size and serviced users.
 We hereby define a data model for TT normalization -- the Network
 Trouble Ticket Data Model (NTTDM) -- initially targeted for network
 providers serving EGEE [8].  The model is designed in accordance with
 RFC 1297 [11] and meets requirements of the multiple TT systems used.
 The NTTDM
 o  is both effective and comprehensive, as it compensates for the
    core activities of the Network Operation Centres (NOCs).  It is
    also dynamic, allowing additional options to be included in the
    future, according to demand.
 o  provides an XML representation for conveying incident information
    across administrative domains between parties that have an
    operational responsibility of remediation or a "watch-and-warn"
    policy over a defined constituency.
 o  encodes information about hosts, networks, and the services
    running on these systems; attack methodology and associated
    forensic evidence; impact of the activity; and limited approaches
    for documenting workflow.
 o  aims to simplify TT exchange within the boundaries of a Grid and
    to enhance the functional cooperation of every NOC and of the Grid
    Operation Centre (GOC).  Community adoption of the NTTDM enhances
    trouble resolution within the Grid framework and imparts network
    status cognizance by modeling collaboration and information
    exchange among operators.

Zisiadis, et al. Experimental [Page 4] RFC 6137 NTTDM February 2011

 o  provides a common format that allows GOCs as well as all
    participating NOCs to store, exchange, manage, and analyze TTs
    (assessment of TT impact).
 o  provides increased automation in handling a TT, since the network
    operators have a common view of the incident.
 The model was designed and used as part of the networking support
 activity of the EGEE project; one of the subtasks of this support
 activity was to enhance the ENOC (EGEE Network Operation Centre) [9]
 procedures for better overall network coordination of the Grid.

1.1. Terminology

 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
 "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
 document are to be interpreted as described in RFC 2119 [1].
 The NTTDM uses specific keywords to describe the various data
 components.  These keywords are:
    Defined, Free, Multiple, List, Predefined String, String,
    Datetime, Solved, Cancelled, Inactive, Superseded, Opened/Closed,
    Operational, Informational, Administrative, and Test.
 These keywords as used in this document are to be interpreted as
 described in Section 2.
 Acronyms:
    TT:    Trouble Ticket
    NTTDM: Network Trouble Ticket Data Model
    DB:    Database
    EGEE:  Enabling Grid for E-sciencE
    ENOC:  EGEE NOC
    NOC:   Network Operation Centre
    GOC:   Grid Operation Centre
    NREN:  National Research and Educational Network
    QoS:   Quality of Service

Zisiadis, et al. Experimental [Page 5] RFC 6137 NTTDM February 2011

    UML:   Unified Modeling Language
    XML:   Extensible Markup Language

1.2. Notations

 The NTTDM is specified in two ways: as an abstract data model and as
 an XML Schema.  Section 3 provides a Unified Modeling Language (UML)
 [10] model describing the individual classes and their relationship
 with each other.  The semantics of each class are discussed and their
 attributes explained.  In Section 6, this UML model is converted into
 an XML Schema [2] [3] [4] [5].  A specific namespace [6] is also
 defined.
 The term "XML document" refers to any instance of an XML Document.
 The term "NTTDM document" refers to specific elements and attributes
 of the NTTDM Schema.  Finally, the terms "class" and "element" are
 used interchangeably to reference either a given UML class in the
 data model or its corresponding Schema implementation.

1.3. About the Network Trouble Ticket Data Model

 The NTTDM is a data representation that provides a framework for
 normalizing and sharing information among network operators and the
 GOC regarding troubles within the Grid boundaries.  There has been a
 lot of thought processing during the design of the data model:
 o  The data model serves as a common storage and exchange format.
 o  Every NOC still uses its home TT system for network management
    within its area of control.
 o  As there is no universally adopted definition for a trouble, in
    the NTTDM definition, the term is used with a comprehensive
    meaning to cover all NOCs.
 o  Handling every possible definition of a trouble incident would
    call for an extremely expanded and complex data model.  Therefore,
    the NTTDM's purpose is to serve as the basis for normalizing and
    exchanging TTs.  It is flexible and expressive in order to ensure
    that specific NOC requirements are met.  Specific NOC information
    is kept outside the NTTDM, and external databases can be used to
    feed it.

Zisiadis, et al. Experimental [Page 6] RFC 6137 NTTDM February 2011

 o  The domain of managing the information is not fully standardized
    and must rely on free-form textual descriptions.  The NTTDM
    attempts to strike a balance between supporting this free-form
    content, while still allowing automated processing of incident
    information.
 The NTTDM is only one of several feasible TT data representations.
 The goal of this design was to be as effective and comprehensive as
 these other representations and to account for the management of a
 general Grid environment.  The already used TT formats influenced the
 design of the NTTDM.

1.4. About the Network Trouble Ticket Implementation

 Here we describe an example of a typical use case.
 The Grid project EGEE manages its infrastructure as a network overlay
 over the European National Research and Educational Networks (NRENs)
 and wants to be able to warn EGEE sites of the unavailability of the
 network.  Thanks to collaboration with its network provider, the EGEE
 NOC receives a high volume of TTs (800 tickets/month, 2500
 emails/month) from 20 NRENs and should always be able to cope with
 such a heavy load.  Thanks to the NTTDM, the EGEE NOC can automate
 the TT workflow:
 o  The TT is filtered, sorted, and stored in a local database (DB).
 o  The TT's impact on the Grid is assessed.
 o  The TT is pushed to an ENOC dashboard application and other tools
    (EGEE TT system, statistics, etc.).

1.5. Future Plans

 Since this is an Experimental document, operational experience will
 be used to expand the subsections of Section 3.2.3, "Ticket Origin
 Information", below.  The current specification is already used
 within EGEE.  Other Grids are free to use it and report comments to
 the authors.  After enough experimentation, we would like to advance
 it to the Standards Track.

2. NTTDM Types and Definitions

 The various data elements of the TT data model are typed.  This
 section discusses these data types.  When possible, native Schema
 data types were adopted, but for more complicated formats, regular
 expressions or external standards were used.

Zisiadis, et al. Experimental [Page 7] RFC 6137 NTTDM February 2011

2.1. Types and Definitions for the TYPE Attribute

 These types are used to describe the TYPE attribute.

2.1.1. Defined

 The Defined data type means that the data model provides a means to
 compute this value from the rest of the fields.
 The Defined data type is implemented as "Defined" in the Schema.

2.1.2. Free

 The Free data type means that the value can be freely chosen.
 All Free strings SHOULD have as an attribute the language used.
 The Free data type is implemented as "Free" in the Schema.

2.1.3. Multiple

 The Multiple data type consists of one value among multiple fixed
 values.
 The Multiple data type is implemented as "Multiple" in the Schema.

2.1.4. List

 "List" means many values among multiple fixed values.  The List data
 type is implemented as "List" in the Schema.

Zisiadis, et al. Experimental [Page 8] RFC 6137 NTTDM February 2011

2.2. Types and Definitions for the VALID FORMAT Attributes

2.2.1. Predefined String

 A Predefined String means the different values are predefined in the
 data model.
 Each field that requires a Predefined String contains a specific
 value.  Figure 1 shows the allowed values for such fields.
 +------------------------+-----------------------------------+
 |         FIELD NAME     |              VALUES               |
 +------------------------+-----------------------------------+
 |          TT_TYPE       |    Operational, Informational,    |
 |                        |       Administrative, Test        |
 +------------------------+-----------------------------------+
 |            TYPE        |      Scheduled, Unscheduled       |
 +------------------------+-----------------------------------+
 |        TT_PRIORITY     |         Low, Medium, High         |
 +------------------------+-----------------------------------+
 |  TT_SHORT_DESCRIPTION  |  Core Line Fault, Access Line     |
 |                        |  Fault, Degraded Service, Router  |
 |                        |  Hardware Fault, Router Software  |
 |                        | Fault, Routing Problem, Undefined |
 |                        |   Problem, Network Congestion,    |
 |                        | Client Upgrade, IPv6, QoS, VoIP,  |
 |                        |               Other               |
 +------------------------+-----------------------------------+
 | TT_IMPACT_ASSESSMENT   |  No impact, Reduced redundancy,   |
 |                        | Minor performance impact, Severe  |
 |                        |      performance impact,          |
 |                        |   No connectivity, On backup,     |
 |                        |       At risk, Unknown            |
 +------------------------+-----------------------------------+
 |        TT_STATUS       | Opened, Updated, Closed, Solved,  |
 |                        |  Inactive, Cancelled, Reopened,   |
 |                        |  Superseded, Opened/Closed        |
 +------------------------+-----------------------------------+
 |       TT_SOURCE        |  Users, Monitoring, Other NOC     |
 +------------------------+-----------------------------------+
              Figure 1.  Allowed Predefined String Values
 The Predefined String data type is implemented as "xs:string" in the
 Schema with a sequence of enumerations for the allowed values.

Zisiadis, et al. Experimental [Page 9] RFC 6137 NTTDM February 2011

2.2.1.1. Definitions of the Predefined Values

 TT_TYPE
 o  Operational: for network incident and maintenance only.
 o  Informational: information about the TT system or the exchange
    interface (maintenance, upgrade).
 o  Administrative: information about the access to the TT system
    (credentials) or the exchange interface.
 o  Test: to test the TT system or the exchange interface, etc.
 TYPE
 o  Scheduled: the incident was scheduled to happen.
 o  Unscheduled: the incident was unscheduled.
 TT_PRIORITY
 o  Low: the TT priority is low.
 o  Medium: the TT priority is medium.
 o  High: the TT priority is high.
 TT_SHORT_DESCRIPTION
 o  Core Line Fault: malfunction of a high-bandwidth core line.
 o  Access Line Fault: malfunction of a medium-bandwidth access line.
 o  Degraded Service.
 o  Router Hardware Fault: malfunction of the router hardware.
 o  Router Software Fault: malfunction of the router software.
 o  Routing Problem: incident regarding the routing service.
 o  Undefined Problem: nature of the problem not identified.
 o  Network Congestion: problem due to traffic at the network
    (blocked).
 o  Client Upgrade: incidents regarding client/services upgrade.

Zisiadis, et al. Experimental [Page 10] RFC 6137 NTTDM February 2011

 o  IPv6: incident regarding the IPv6 network.
 o  QoS: incident regarding the Quality of Service (QoS) of the
    network.
 o  VoIP: incident regarding Voice over IP (VoIP).
 o  Other: non-listed incident.
 TT_IMPACT_ASSESSMENT
 o  No impact: the incident does not cause any impacts.
 o  Reduced redundancy: the incident reduces network redundancy.
 o  Minor performance impact: the incident causes a minor performance
    impact.
 o  Severe performance impact: the incident causes a severe
    performance impact.
 o  No connectivity: the incident causes connectivity failure.
 o  On backup: the incident causes a malfunction of backup services.
 o  At risk: the incident should not have any impact but could
    possibly cause some trouble.
 o  Unknown: the nature of the impact is not identified.
 TT_STATUS
 o  Opened: the ticket is opened.
 o  Closed: the ticket is closed.
 o  Updated: the ticket's contents have been updated.
 o  Cancelled: the ticket has been opened twice; one of the tickets is
    cancelled, and a relationship between them is defined via the
    RELATED_ACTIVITY field.
 o  Solved: the incident is solved, but the team prefers to
    monitor/check for future issues.
 o  Opened/Closed: the ticket was opened only to report an incident
    that has already been solved.

Zisiadis, et al. Experimental [Page 11] RFC 6137 NTTDM February 2011

 o  Inactive: the ticket is under the responsibility of an external
    domain and is no longer under the reporting domain's control.
 o  Reopened: the ticket was closed by error, or the problem was
    erroneously declared to be solved.  Data in the History field are
    very important in this case.
 o  Superseded: the ticket has been superseded by another one (for
    example, a bigger problem that had resulted in many tickets was
    later merged into a single incident/ticket).  The RELATED_ACTIVITY
    field SHOULD include the master ticket reference.
 Allowed transitions for TT_STATUS are only those indicated in
 Figure 2.  Possible final states are indicated with (X).

Zisiadis, et al. Experimental [Page 12] RFC 6137 NTTDM February 2011

                         +------------------+
                         | Opened/Closed (X)|
                         +------------------+
                                  |
                                  |
                                  V
                           +--------------+
   /-----------------------|  Reopened    |<-------------------\
   |                       |              |----------\         |
   |                       +--------------+          |         |
   |                             ^                   |         |
   |                             |                   |         |
   |                             V                   |         |
   |                     +-------------------+       |         |
   |                     | Superseded    (X) |       |         |
   |                     | or Inactive   (X) |       |         |
   |  /----------------->| or Cancelled  (X) |<---\  |         |
   |  |                  +-------------------+    |  |         |
   |  |                          ^                |  |         |
   |  |                          |                |  V         |
   |  |            +--------+    |            +--------+       |
   |  |  /---------| Opened |----/            | Solved |-----\ |
   |  |  |         |        |---------------->|        |     | |
   |  |  |         +--------+                 +--------+     | |
   |  |  |             |                          ^          | |
   V  |  V             |                          |          | |
 +---------+           |                          |          | |
 |         |----------(|)-------------------------/          V V
 | Updated |           |                              +------------+
 |         |----------(|)---------------------------->|            |
 +---------+           |                              | Closed (X) |
                       \----------------------------->|            |
                                                      +------------+
                Figure 2.  TT_STATUS Transition Diagram

2.2.2. String

 The String value is defined by the user of the model.  The String
 data type is implemented as "xs:string" in the Schema.

2.2.3. Datetime

 Date-time strings are represented by the Datetime data type.  Each
 date-time string identifies a particular instant in time; ranges are
 not supported.

Zisiadis, et al. Experimental [Page 13] RFC 6137 NTTDM February 2011

 Date-time strings are formatted according to a subset of
 ISO 8601:2000 as documented in RFC 3339.
 The Datetime data type is implemented as "xs:dateTime" in the Schema.

3. NTTDM

 In this section, the individual components of the NTTDM will be
 discussed in detail.  This class provides a standardized
 representation for commonly exchanged Field Name data.

3.1. NTTDM Components

3.1.1. NTTDM Attributes

 The Field Name class has four attributes.  Each attribute provides
 information about a Field Name instance.  The attributes that
 characterize one instance constitute all the information required to
 form the data model.
 DESCRIPTION
    This field contains a short description of the Field Name.
 TYPE
    The TYPE attribute contains information about the type of the
    Field Name it depends on.  The values that it may contain are:
    Defined, Free, Multiple, and List.
 VALID FORMAT
    This attribute contains information about the format of each
    field.  The values that it may contain are:
    Predefined String, String, and Datetime.
 MANDATORY
    This attribute indicates whether the information of each field is
    required or optional.  If the information is required, the
    MANDATORY field contains the word "YES".  If the information is
    optional, the MANDATORY field contains the word "NO".

Zisiadis, et al. Experimental [Page 14] RFC 6137 NTTDM February 2011

3.2. NTTDM Aggregate Classes

3.2.1. NTTDM-Document Class

 The NTTDM-Document class is the top-level class in the NTTDM.  All
 NTTDM documents are an instance of this class.
            +---------------+
            | NTTDM-Document|
            +---------------+
            | version       |<>--{1..*}--[ Ticket     ]
            | lang          |
            +---------------+
                    Figure 3.  NTTDM-Document Class
 The aggregate class that constitutes an NTTDM-Document is:
 Ticket
    One or more.  The information related to a single ticket.
 The NTTDM-Document class has two attributes:
 version
    STRING.  The value of this attribute MUST be "1.00".
 lang
    Required.

3.2.2. Ticket Class

 Every ticket is represented by an instance of the Ticket class.  This
 class provides a standardized representation for commonly exchanged
 TT data.

Zisiadis, et al. Experimental [Page 15] RFC 6137 NTTDM February 2011

      +---------+
      | Ticket  |
      +---------+
      |  lang   |<>----------[ Partner_ID               ]
      |         |<>----------[ Original_ID              ]
      |         |<>----------[ TT_ID                    ]
      |         |<>----------[ TT_Title                 ]
      |         |<>----------[ TT_Type                  ]
      |         |<>--{0..1}--[ TT_Priority              ]
      |         |<>----------[ TT_Status                ]
      |         |<>--{0..1}--[ TT_Source                ]
      |         |<>----------[ TT_Open_Datetime         ]
      |         |<>----------[ TT_Close_Datetime        ]
      |         |<>----------[ TT_Short_Description     ]
      |         |<>----------[ TT_Long_Description      ]
      |         |<>----------[ Type                     ]
      |         |<>----------[ TT_Impact_Assessment     ]
      |         |<>----------[ Start_Datetime           ]
      |         |<>--{0..1}--[ Detect_Datetime          ]
      |         |<>--{0..1}--[ Report_Datetime          ]
      |         |<>----------[ End_Datetime             ]
      |         |<>----------[ TT_Last_Update_Time      ]
      |         |<>--{0..1}--[ Time_Window_Start        ]
      |         |<>--{0..1}--[ Time_Window_End          ]
      |         |<>--{0..1}--[ Work_Plan_Start_Datetime ]
      |         |<>--{0..1}--[ Work_Plan_End_Datetime   ]
      |         |<>--{0..1}--[ Related_External_Tickets ]
      |         |<>--{0..1}--[ Additional_Data          ]
      |         |<>--{0..1}--[ Related_Activity         ]
      |         |<>----------[ History                  ]
      |         |<>--{0..1}--[ Affected_Community       ]
      |         |<>--{0..1}--[ Affected_Service         ]
      |         |<>----------[ Location                 ]
      |         |<>--{0..1}--[ Network_Node             ]
      |         |<>--{0..1}--[ Network_Link_Circuit     ]
      |         |<>--{0..1}--[ End_Line_Location_A      ]
      |         |<>--{0..1}--[ End_Line_Location_B      ]
      |         |<>--{0..1}--[ Open_Engineer            ]
      |         |<>--{0..1}--[ Contact_Engineers        ]
      |         |<>--{0..1}--[ Close_Engineer           ]
      |         |<>--{0..1}--[ Hash                     ]
      +---------+
                      Figure 4.  The Ticket Class
 lang
    Required.

Zisiadis, et al. Experimental [Page 16] RFC 6137 NTTDM February 2011

 The Field Names are the Aggregate Classes that constitute the NTTDM,
 and each of them is an element that is characterized by a quadruple
 (DESCRIPTION, TYPE, VALID FORMAT, MANDATORY).

3.2.3. Ticket Origin Information

3.2.3.1. PARTNER_ID

    +--------------+
    | PARTNER_ID   |
    +--------------+
    | DESCRIPTION  |   The unique ID of the TT source partner.
    | TYPE         |   Multiple.
    | VALID FORMAT |   String.
    | MANDATORY    |   Yes.
    +--------------+
                      Figure 5.  Partner_ID Class

3.2.3.2. ORIGINAL_ID

    +--------------+
    | ORIGINAL_ID  |
    +--------------+
    | DESCRIPTION  |   The TT ID that was assigned by the party.
    | TYPE         |   Free.
    | VALID FORMAT |   String.
    | MANDATORY    |   Yes.
    +--------------+
                     Figure 6.  Original_ID Class

3.2.4. Ticket Information

3.2.4.1. TT_ID

    +--------------+
    | TT_ID        |
    +--------------+
    | DESCRIPTION  |   The unique ID of the TT.
    | TYPE         |   As defined below.
    | VALID FORMAT |   String.
    | MANDATORY    |   Yes.
    +--------------+
                        Figure 7.  TT_ID Class

Zisiadis, et al. Experimental [Page 17] RFC 6137 NTTDM February 2011

 TYPE is constructed as "PARTNER_ID"_"ORIGINAL_ID".  PARTNER_ID and
 ORIGINAL_ID therefore MUST NOT contain an underscore character.

3.2.4.2. TT_TITLE

    +---------------+
    | TT_TITLE      |
    +---------------+
    | DESCRIPTION   |   The title of the TT.
    | TYPE          |   Defined.
    | VALID FORMAT  |   String.
    | MANDATORY     |   Yes.
    +---------------+
                       Figure 8.  TT_Title Class

3.2.4.3. TT_TYPE

    +---------------+
    | TT_TYPE       |
    +---------------+
    | DESCRIPTION   |   The type of the TT.
    | TYPE          |   Multiple.
    | VALID FORMAT  |   Predefined String.
    | MANDATORY     |   Yes.
    +---------------+
                       Figure 9.  TT_Type Class

3.2.4.4. TT_PRIORITY

    +--------------+
    | TT_PRIORITY  |
    +--------------+
    | DESCRIPTION  |   The TT priority.
    | TYPE         |   Multiple.
    | VALID FORMAT |   Predefined String.
    | MANDATORY    |   No.
    +--------------+
                     Figure 10.  TT_Priority Class

Zisiadis, et al. Experimental [Page 18] RFC 6137 NTTDM February 2011

3.2.4.5. TT_STATUS

    +--------------+
    | TT_STATUS    |
    +--------------+
    | DESCRIPTION  |   The TT status.
    | TYPE         |   Multiple.
    | VALID FORMAT |   Predefined String.
    | MANDATORY    |   Yes.
    +--------------+
                      Figure 11.  TT_Status Class

3.2.4.6. TT_SOURCE

    +--------------+
    | TT_SOURCE    |
    +--------------+
    | DESCRIPTION  |   The source of the ticket.
    | TYPE         |   Multiple.
    | VALID FORMAT |   Predefined String.
    | MANDATORY    |   No.
    +--------------+
                      Figure 12.  TT_Source Class

3.2.4.7. TT_OPEN_DATETIME

    +------------------+
    | TT_OPEN_DATETIME |
    +------------------+
    | DESCRIPTION      |   The date and time when the TT was opened.
    | TYPE             |   Multiple.
    | VALID FORMAT     |   Datetime.
    | MANDATORY        |   Yes.
    +------------------+
                  Figure 13.  TT_Open_Datetime Class

Zisiadis, et al. Experimental [Page 19] RFC 6137 NTTDM February 2011

3.2.4.8. TT_CLOSE_DATETIME

    +-------------------+
    | TT_CLOSE_DATETIME |
    +-------------------+
    | DESCRIPTION       |   The date and time when the TT was closed.
    | TYPE              |   Multiple.
    | VALID FORMAT      |   Datetime.
    | MANDATORY         |   Yes.
    +-------------------+
                  Figure 14.  TT_Close_Datetime Class

3.2.5. Trouble Details

3.2.5.1. TT_SHORT_DESCRIPTION

    +----------------------+
    | TT_SHORT_DESCRIPTION |
    +----------------------+
    | DESCRIPTION          |   The short description of the trouble.
    | TYPE                 |   Multiple.
    | VALID FORMAT         |   Predefined String.
    | MANDATORY            |   Yes.
    +----------------------+
                Figure 15.  TT_Short_Description Class

3.2.5.2. TT_LONG_DESCRIPTION

    +---------------------+
    | TT_LONG_DESCRIPTION |
    +---------------------+
    | DESCRIPTION         |   The detailed description of the
    |                     |   incident/maintenance reported in the TT.
    | TYPE                |   Free.
    | VALID FORMAT        |   String.
    | MANDATORY           |   No.
    +---------------------+
                 Figure 16.  TT_Long_Description Class

Zisiadis, et al. Experimental [Page 20] RFC 6137 NTTDM February 2011

3.2.5.3. TYPE

    +--------------+
    | TYPE         |
    +--------------+
    | DESCRIPTION  |   The type of the trouble.
    | TYPE         |   Multiple.
    | VALID FORMAT |   Predefined String.
    | MANDATORY    |   Yes.
    +--------------+
                        Figure 17.  Type Class

3.2.5.4. TT_IMPACT_ASSESSMENT

   +----------------------+
   | TT_IMPACT_ASSESSMENT |
   +----------------------+
   | DESCRIPTION          |   The impact of the incident/maintenance.
   | TYPE                 |   Multiple.
   | VALID FORMAT         |   Predefined String.
   | MANDATORY            |   Yes.
   +----------------------+
                Figure 18.  TT_Impact_Assessment Class

3.2.5.5. START_DATETIME

    +----------------+
    | START_DATETIME |
    +----------------+
    | DESCRIPTION    |   The date and time that the
    |                |   incident/maintenance started.
    | TYPE           |   Multiple.
    | VALID FORMAT   |   Datetime.
    | MANDATORY      |   Yes.
    +----------------+
                   Figure 19.  Start_Datetime Class

Zisiadis, et al. Experimental [Page 21] RFC 6137 NTTDM February 2011

3.2.5.6. DETECT_DATETIME

    +-------------------+
    | DETECT_DATETIME   |
    +-------------------+
    | DESCRIPTION       |   The date and time when the incident
    |                   |   was detected.
    | TYPE              |   Multiple.
    | VALID FORMAT      |   Datetime.
    | MANDATORY         |   No.
    +-------------------+
                   Figure 20.  Detect_Datetime Class

3.2.5.7. REPORT_DATETIME

   +-----------------+
   | REPORT_DATETIME |
   +-----------------+
   | DESCRIPTION     |   The date and time when the incident
   |                 |   was reported.
   | TYPE            |   Multiple.
   | VALID FORMAT    |   Datetime.
   | MANDATORY       |   No.
   +-----------------+
                   Figure 21.  Report_Datetime Class

3.2.5.8. END_DATETIME

   +--------------+
   | END_DATETIME |
   +--------------+
   | DESCRIPTION  |   The date and time when the incident/maintenance
   |              |   ended.
   | TYPE         |   Multiple.
   | VALID FORMAT |   Datetime.
   | MANDATORY    |   Yes.
   +--------------+
                    Figure 22.  End_Datetime Class

Zisiadis, et al. Experimental [Page 22] RFC 6137 NTTDM February 2011

3.2.5.9. TT_LAST_UPDATE_TIME

    +---------------------+
    | TT_LAST_UPDATE_TIME |
    +---------------------+
    | DESCRIPTION         |   The last date and time when the TT was
    |                     |   updated.
    | TYPE                |   Multiple.
    | VALID FORMAT        |   Datetime.
    | MANDATORY           |   Yes.
    +---------------------+
                 Figure 23.  TT_Last_Update_Time Class

3.2.5.10. TIME_WINDOW_START

    +-------------------+
    | TIME_WINDOW_START |
    +-------------------+
    | DESCRIPTION       |   The window start time in which planned
    |                   |   maintenance may occur.
    | TYPE              |   Multiple.
    | VALID FORMAT      |   Datetime.
    | MANDATORY         |   No, unless TYPE is "Scheduled".
    +-------------------+
                  Figure 24.  Time_Window_Start Class

3.2.5.11. TIME_WINDOW_END

    +-----------------+
    | TIME_WINDOW_END |
    +-----------------+
    | DESCRIPTION     |   The window end time in which planned
    |                 |   maintenance may occur.
    | TYPE            |   Multiple.
    | VALID FORMAT    |   Datetime.
    | MANDATORY       |   No, unless TYPE is "Scheduled".
    +-----------------+
                   Figure 25.  Time_Window_End Class

Zisiadis, et al. Experimental [Page 23] RFC 6137 NTTDM February 2011

3.2.5.12. WORK_PLAN_START_DATETIME

    +--------------------------+
    | WORK_PLAN_START_DATETIME |
    +--------------------------+
    | DESCRIPTION              |   Work planned (expected): start time
    |                          |   in case of maintenance.
    | TYPE                     |   Multiple.
    | VALID FORMAT             |   Datetime.
    | MANDATORY                |   No.
    +--------------------------+
              Figure 26.  Work_Plan_Start_Datetime Class

3.2.5.13. WORK_PLAN_END_DATETIME

    +------------------------+
    | WORK_PLAN_END_DATETIME |
    +------------------------+
    | DESCRIPTION            |   Work planned (expected): end time
    |                        |   in case of maintenance.
    | TYPE                   |   Multiple.
    | VALID FORMAT           |   Datetime.
    | MANDATORY              |   No.
    +------------------------+
               Figure 27.  Work_Plan_End_Datetime Class
 The period delimited by WORK_PLAN_START_DATETIME and
 WORK_PLAN_END_DATETIME MUST be included in the period delimited by
 TIME_WINDOW_START and TIME_WINDOW_END, and duplicated with {START,
 END}_DATETIME, even in case of maintenance.

3.2.6. Related Data

3.2.6.1. RELATED_EXTERNAL_TICKETS

 +--------------------------+
 | RELATED_EXTERNAL_TICKETS |
 +--------------------------+
 | DESCRIPTION              |  The NOC entity related to the incident.
 | TYPE                     |  List.
 | VALID FORMAT             |  String.
 | MANDATORY                |  No.
 +--------------------------+
              Figure 28.  Related_External_Tickets Class

Zisiadis, et al. Experimental [Page 24] RFC 6137 NTTDM February 2011

3.2.6.2. ADDITIONAL_DATA

    +-----------------+
    | ADDITIONAL_DATA |
    +-----------------+
    | DESCRIPTION     |   Additional information.
    | TYPE            |   Free.
    | VALID FORMAT    |   String.
    | MANDATORY       |   No.
    +-----------------+
                   Figure 29.  Additional_Data Class

3.2.6.3. RELATED_ACTIVITY

    +------------------+
    | RELATED_ACTIVITY |
    +------------------+
    | DESCRIPTION      |   The TT IDs of the related incidents.
    | TYPE             |   Multiple.
    | VALID FORMAT     |   String.
    | MANDATORY        |   No.
    +------------------+
                  Figure 30.  Related_Activity Class

3.2.6.4. HISTORY

    +--------------+
    | HISTORY      |
    +--------------+
    | DESCRIPTION  |   The necessary actions/events log.
    | TYPE         |   Free.
    | VALID FORMAT |   String.
    | MANDATORY    |   Yes.
    +--------------+
                       Figure 31.  History Class
    Note: This field MUST NOT be empty when the VALID FORMAT attribute
    of the TT_STATUS field is anything other than "OPENED" or
    "OPENED/CLOSED".

Zisiadis, et al. Experimental [Page 25] RFC 6137 NTTDM February 2011

3.2.7. Localization and Impact

3.2.7.1. AFFECTED_COMMUNITY

    +--------------------+
    | AFFECTED_COMMUNITY |
    +--------------------+
    | DESCRIPTION        |   Information about the community that was
    |                    |   affected by the incident.
    | TYPE               |   Free.
    | VALID FORMAT       |   String.
    | MANDATORY          |   No.
    +--------------------+
                 Figure 32.  Affected_Community Class

3.2.7.2. AFFECTED_SERVICE

    +------------------+
    | AFFECTED_SERVICE |
    +------------------+
    | DESCRIPTION      |   The service that was affected by the
    |                  |   incident.
    | TYPE             |   Multiple.
    | VALID FORMAT     |   String.
    | MANDATORY        |   No.
    +------------------+
                  Figure 33.  Affected_Service Class

3.2.7.3. LOCATION

    +--------------+
    | LOCATION     |
    +--------------+
    | DESCRIPTION  |   The location (Point of Presence (POP) site,
    |              |   city, etc.) of the incident/maintenance.
    | TYPE         |   Multiple.
    | VALID FORMAT |   String.
    | MANDATORY    |   Yes.
    +--------------+
                      Figure 34.  Location Class

Zisiadis, et al. Experimental [Page 26] RFC 6137 NTTDM February 2011

3.2.7.4. NETWORK_NODE

    +--------------+
    | NETWORK_NODE |
    +--------------+
    | DESCRIPTION  |   The NOC network node related to the incident.
    | TYPE         |   List.
    | VALID FORMAT |   String.
    | MANDATORY    |   No.
    +--------------+
                    Figure 35.  Network_Node Class

3.2.7.5. NETWORK_LINK_CIRCUIT

    +----------------------+
    | NETWORK_LINK_CIRCUIT |
    +----------------------+
    | DESCRIPTION          |   The name of the network line related
    |                      |   to the incident.
    | TYPE                 |   List.
    | VALID FORMAT         |   String.
    | MANDATORY            |   No.
    +----------------------+
                Figure 36.  Network_Link_Circuit Class

3.2.7.6. END_LINE_LOCATION_A

    +---------------------+
    | END_LINE_LOCATION_A |
    +---------------------+
    | DESCRIPTION         |   A-end of the link.
    | TYPE                |   Multiple.
    | VALID FORMAT        |   String.
    | MANDATORY           |   No.
    +---------------------+
                 Figure 37.  End_Line_Location_A Class

Zisiadis, et al. Experimental [Page 27] RFC 6137 NTTDM February 2011

3.2.7.7. END_LINE_LOCATION_B

    +---------------------+
    | END_LINE_LOCATION_B |
    +---------------------+
    | DESCRIPTION         |   B-end of the link.
    | TYPE                |   Multiple.
    | VALID FORMAT        |   String.
    | MANDATORY           |   No.
    +---------------------+
                 Figure 38.  End_Line_Location_B Class

3.2.8. Contact Information

3.2.8.1. OPEN_ENGINEER

    +---------------+
    | OPEN_ENGINEER |
    +---------------+
    | DESCRIPTION   |   The engineer that opened the ticket.
    | TYPE          |   Multiple.
    | VALID FORMAT  |   String.
    | MANDATORY     |   No.
    +---------------+
                    Figure 39.  Open_Engineer Class

3.2.8.2. CONTACT_ENGINEERS

    +-------------------+
    | CONTACT_ENGINEERS |
    +-------------------+
    | DESCRIPTION       |   The engineers responsible for the incident
    |                   |   settlement.
    | TYPE              |   List.
    | VALID FORMAT      |   String.
    | MANDATORY         |   No.
    +-------------------+
                  Figure 40.  Contact_Engineers Class

Zisiadis, et al. Experimental [Page 28] RFC 6137 NTTDM February 2011

3.2.8.3. CLOSE_ENGINEER

    +----------------+
    | CLOSE_ENGINEER |
    +----------------+
    | DESCRIPTION    |   The engineer that closed the ticket.
    | TYPE           |   Multiple.
    | VALID FORMAT   |   String.
    | MANDATORY      |   No.
    +----------------+
                   Figure 41.  Close_Engineer Class

3.2.9. Security

3.2.9.1. HASH

    +-------------+
    | HASH        |
    +-------------+
    | DESCRIPTION |   Encrypted message hash.
    | TYPE        |   Defined.
    | VALID FORMAT|   String.
    | MANDATORY   |   No.
    +-------------+
                        Figure 42.  Hash Class

3.3. NTTDM Representation

 The collected and processed TTs received from multiple
 telecommunications networks are adjusted in a normalized NTTDM.
 Figure 43 shows the representation of this normalized data model.
 The "DESCRIPTION" attribute is implied.

Zisiadis, et al. Experimental [Page 29] RFC 6137 NTTDM February 2011

 +------------------------+--------+------------------+---------+
 | FIELD NAME             | TYPE   |VALID FORMAT      |MANDATORY|
 +------------------------+--------+------------------+---------+
 |PARTNER_ID              |MULTIPLE|STRING            |YES      |
 |ORIGINAL_ID             |FREE    |STRING            |YES      |
 |TT_ID                   |DEFINED |STRING            |YES      |
 |TT_TITLE                |DEFINED |STRING            |YES      |
 |TT_TYPE                 |MULTIPLE|PREDEFINED STRING |YES      |
 |TT_PRIORITY             |MULTIPLE|PREDEFINED STRING |NO       |
 |TT_STATUS               |MULTIPLE|PREDEFINED STRING |YES      |
 |TT_SOURCE               |MULTIPLE|PREDEFINED STRING |NO       |
 |TT_OPEN_DATETIME        |MULTIPLE|DATETIME          |YES      |
 |TT_CLOSE_DATETIME       |MULTIPLE|DATETIME          |YES      |
 |TT_SHORT_DESCRIPTION    |MULTIPLE|PREDEFINED STRING |YES      |
 |TT_LONG_DESCRIPTION     |FREE    |STRING            |NO       |
 |TYPE                    |MULTIPLE|PREDEFINED STRING |YES      |
 |TT_IMPACT_ASSESSMENT    |MULTIPLE|PREDEFINED STRING |YES      |
 |START_DATETIME          |MULTIPLE|DATETIME          |YES      |
 |DETECT_DATETIME         |MULTIPLE|DATETIME          |NO       |
 |REPORT_DATETIME         |MULTIPLE|DATETIME          |NO       |
 |END_DATETIME            |MULTIPLE|DATETIME          |YES      |
 |TT_LAST_UPDATE_TIME     |MULTIPLE|DATETIME          |YES      |
 |TIME_WINDOW_START       |MULTIPLE|DATETIME          |NO       |
 |TIME_WINDOW_END         |MULTIPLE|DATETIME          |NO       |
 |WORK_PLAN_START_DATETIME|MULTIPLE|DATETIME          |NO       |
 |WORK_PLAN_END_DATETIME  |MULTIPLE|DATETIME          |NO       |
 |RELATED_EXTERNAL_TICKETS|LIST    |STRING            |NO       |
 |ADDITIONAL_DATA         |FREE    |STRING            |NO       |
 |RELATED_ACTIVITY        |MULTIPLE|STRING            |NO       |
 |HISTORY                 |FREE    |STRING            |YES      |
 |AFFECTED_COMMUNITY      |FREE    |STRING            |NO       |
 |AFFECTED_SERVICE        |MULTIPLE|STRING            |NO       |
 |LOCATION                |MULTIPLE|STRING            |YES      |
 |NETWORK_NODE            |LIST    |STRING            |NO       |
 |NETWORK_LINK_CIRCUIT    |LIST    |STRING            |NO       |
 |END_LINE_LOCATION_A     |MULTIPLE|STRING            |NO       |
 |END_LINE_LOCATION_B     |MULTIPLE|STRING            |NO       |
 |OPEN_ENGINEER           |MULTIPLE|STRING            |NO       |
 |CONTACT_ENGINEERS       |LIST    |STRING            |NO       |
 |CLOSE_ENGINEER          |MULTIPLE|STRING            |NO       |
 |HASH                    |DEFINED |STRING            |NO       |
 +------------------------+--------+------------------+---------+
                   Figure 43.  The Field Name Class

Zisiadis, et al. Experimental [Page 30] RFC 6137 NTTDM February 2011

4. Internationalization Issues

 Internationalization and localization are of specific concern to the
 NTTDM, since it is only through collaboration, often across language
 barriers, that certain incidents can be resolved.  The NTTDM supports
 this goal by depending on XML constructs, and through explicit design
 choices in the data model.
 The main advantage of the model is that it provides a normalized data
 type that is implemented fully in the English language and can be
 used conveniently.  It also supports free-formed text that can be
 written in any language.  In the future, it will provide translation
 services for all such free-formed text.

5. Example

5.1. Link Failure

 In this section, an example of network TTs exchanged using the
 proposed format is provided.  This is an actual GRNet ticket
 normalized according to the NTTDM.  Fields that were not included in
 the ticket are left blank.
 <?xml version="1.0" encoding="UTF-8"?>
 <!-- This example describes a link failure that was detected -->
 <NTTDM-Document version="1.00" lang="el"
                 xmlns="urn:ietf:params:xml:ns:nttdm-1.0">
 <Ticket>
  <Original_ID>5985</Original_ID>
  <Partner_ID>01</Partner_ID>
  <TT_ID>01_5985</TT_ID>
  <TT_Title>Forth Link Failure</TT_Title>
  <TT_Type>Operational</TT_Type>
  <TT_Status>Closed</TT_Status>
  <TT_Open_Datetime>2008-12-16T10:01:15+02:00</TT_Open_Datetime>
  <TT_Short_Description>Core Line Fault</TT_Short_Description>
  <TT_Long_Description>Forth Link Failure</TT_Long_Description>
  <Type>Unscheduled</Type>
  <TT_Impact_Assessment>No connectivity</TT_Impact_Assessment>
  <Start_Datetime>2008-12-16T09:55:00+02:00</Start_Datetime>
  <TT_Last_Update_Time>2008-12-16T15:00:34+02:00</TT_Last_Update_Time>
  <Location>HERAKLION</Location>
  <History>Optical transmitter was changed</History>
  <TT_Close_Datetime>2008-12-16T15:05:00+02:00</TT_Close_Datetime>
  <End_Datetime>2008-12-16T15:01:21+02:00</End_Datetime>

Zisiadis, et al. Experimental [Page 31] RFC 6137 NTTDM February 2011

  <Network_Node>
   <Node>FORTH</Node>
  </Network_Node>
  <Network_Link_Circuit>
   <Link_Circuit>FORTH-2</Link_Circuit>
  </Network_Link_Circuit>
  <Open_Engineer>Dimitris Zisiadis</Open_Engineer>
  <Close_Engineer>Guillaume Cessieux</Close_Engineer>
  <Contact_Engineers>
   <Engineer>Spyros Kopsidas</Engineer>
   <Engineer>Chrysostomos Tziouvaras</Engineer>
  </Contact_Engineers>
  <TT_Priority>High</TT_Priority>
 </Ticket>
 </NTTDM-Document>

6. Sample Implementation: XML Schema

 This section provides a sample XML Schema of the NTTDM.
 <?xml version="1.0" encoding="UTF-8" ?>
 <xs:schema xmlns="urn:ietf:params:xml:ns:nttdm-0.1"
  xmlns:nttdm="urn:ietf:params:xml:ns:nttdm-1.0"
  xmlns:xs="http://www.w3.org/2001/XMLSchema"
  targetNamespace="urn:ietf:params:xml:ns:nttdm-1.0"
  elementFormDefault="qualified"
  attributeFormDefault="unqualified">
  <xs:annotation>
   <xs:documentation
       >Trouble Ticket Data Model v-1.0</xs:documentation>
  </xs:annotation>
  <!--
  ===============================================================
  == NTTDM-Document Class                                      ==
  ===============================================================
  -->
  <xs:element name="NTTDM-Document">
   <xs:complexType>
    <xs:sequence>
     <xs:element ref="nttdm:Ticket" maxOccurs="unbounded"/>
    </xs:sequence>
    <xs:attribute name="version" type="xs:string" fixed="1.00"/>
    <xs:attribute name="lang" type="xs:language" use="required"/>
   </xs:complexType>
  </xs:element>

Zisiadis, et al. Experimental [Page 32] RFC 6137 NTTDM February 2011

  <!--
  ===============================================================
  ==  Ticket Class                                             ==
  ===============================================================
  -->
  <xs:element name="Ticket">
    <xs:complexType>
     <xs:all>
      <xs:element ref="nttdm:Partner_ID"/>
      <xs:element ref="nttdm:Original_ID"/>
      <xs:element ref="nttdm:TT_ID"/>
      <xs:element ref="nttdm:TT_Title"/>
      <xs:element ref="nttdm:TT_Type"/>
      <xs:element ref="nttdm:TT_Priority" minOccurs="0"/>
      <xs:element ref="nttdm:TT_Status"/>
      <xs:element ref="nttdm:TT_Source" minOccurs="0"/>
      <xs:element ref="nttdm:TT_Open_Datetime"/>
      <xs:element ref="nttdm:TT_Close_Datetime"/>
      <xs:element ref="nttdm:TT_Short_Description"/>
      <xs:element ref="nttdm:TT_Long_Description"/>
      <xs:element ref="nttdm:Type"/>
      <xs:element ref="nttdm:TT_Impact_Assessment"/>
      <xs:element ref="nttdm:Start_Datetime"/>
      <xs:element ref="nttdm:Detect_Datetime" minOccurs="0"/>
      <xs:element ref="nttdm:Report_Datetime" minOccurs="0"/>
      <xs:element ref="nttdm:End_Datetime"/>
      <xs:element ref="nttdm:TT_Last_Update_Time"/>
      <xs:element ref="nttdm:Time_Window_Start" minOccurs="0"/>
      <xs:element ref="nttdm:Time_Window_End" minOccurs="0"/>
      <xs:element ref="nttdm:Work_Plan_Start_Datetime" minOccurs="0"/>
      <xs:element ref="nttdm:Work_Plan_End_Datetime" minOccurs="0"/>
      <xs:element ref="nttdm:Related_External_Tickets" minOccurs="0"/>
      <xs:element ref="nttdm:Additional_Data" minOccurs="0"/>
      <xs:element ref="nttdm:Related_Activity" minOccurs="0"/>
      <xs:element ref="nttdm:History"/>
      <xs:element ref="nttdm:Affected_Community" minOccurs="0"/>
      <xs:element ref="nttdm:Affected_Service" minOccurs="0"/>
      <xs:element ref="nttdm:Location"/>
      <xs:element ref="nttdm:Network_Node" minOccurs="0"/>
      <xs:element ref="nttdm:Network_Link_Circuit" minOccurs="0"/>
      <xs:element ref="nttdm:End_Line_Location_B" minOccurs="0"/>
      <xs:element ref="nttdm:Open_Engineer" minOccurs="0"/>
      <xs:element ref="nttdm:Contact_Engineers" minOccurs="0"/>
      <xs:element ref="nttdm:Close_Engineer" minOccurs="0"/>
      <xs:element ref="nttdm:Hash" minOccurs="0"/>
      <xs:element ref="nttdm:End_Line_Location_A" minOccurs="0"/>
     </xs:all>

Zisiadis, et al. Experimental [Page 33] RFC 6137 NTTDM February 2011

    <xs:attribute name="lang" type="xs:language"/>
   </xs:complexType>
  </xs:element>
  <!--
  ===============================================================
  ==  Partner_ID Class                                         ==
  ===============================================================
  -->
  <xs:element name="Partner_ID" type="nttdm:string_no_underscore"/>
  <!--
  ===============================================================
  ==  Original_ID Class                                        ==
  ===============================================================
  -->
  <xs:element name="Original_ID" type="nttdm:string_no_underscore"/>
  <!--
  ===============================================================
  ==  TT_ID Class                                              ==
  ===============================================================
  -->
  <xs:element name="TT_ID" type="xs:string"/>
  <!--
  ===============================================================
  ==  TT_Title Class                                           ==
  ===============================================================
  -->
  <xs:element name="TT_Title" type="xs:string"/>
  <!--
  ===============================================================
  ==  TT_Type Class                                            ==
  ===============================================================
  -->
  <xs:element name="TT_Type" type="nttdm:eTT_Type"/>
  <!--
  ===============================================================
  ==  TT_Priority Class                                        ==
  ===============================================================
  -->
  <xs:element name="TT_Priority" type="nttdm:eTT_Priority"/>

Zisiadis, et al. Experimental [Page 34] RFC 6137 NTTDM February 2011

  <!--
  ===============================================================
  ==  TT_Status Class                                          ==
  ===============================================================
  -->
  <xs:element name="TT_Status" type="nttdm:eTT_Status"/>
  <!--
  ===============================================================
  ==  TT_Source Class                                          ==
  ===============================================================
  -->
  <xs:element name="TT_Source" type="nttdm:eTT_Source"/>
  <!--
  ===============================================================
  ==  TT_Open_Datetime Class                                   ==
  ===============================================================
  -->
  <xs:element name="TT_Open_Datetime" type="xs:dateTime"/>
  <!--
  ===============================================================
  ==  TT_Close_Datetime Class                                  ==
  ===============================================================
  -->
  <xs:element name="TT_Close_Datetime" type="xs:dateTime"/>
  <!--
  ===============================================================
  ==  TT_Short_Description Class                               ==
  ===============================================================
  -->
  <xs:element name="TT_Short_Description"
              type="nttdm:eTT_Short_Description"/>
  <!--
  ===============================================================
  ==  TT_Long_Description Class                                ==
  ===============================================================
  -->
  <xs:element name="TT_Long_Description" type="xs:string"/>

Zisiadis, et al. Experimental [Page 35] RFC 6137 NTTDM February 2011

  <!--
  ===============================================================
  ==  Type Class                                               ==
  ===============================================================
  -->
  <xs:element name="Type" type="nttdm:eType"/>
  <!--
  ===============================================================
  ==  TT_Impact_Assessment Class                               ==
  ===============================================================
  -->
  <xs:element name="TT_Impact_Assessment"
           type="nttdm:eTT_Impact_Assessment"/>
  <!--
  ===============================================================
  ==  Start_Datetime Class                                     ==
  ===============================================================
  -->
  <xs:element name="Start_Datetime" type="xs:dateTime"/>
  <!--
  ===============================================================
  ==  Detect_Datetime Class                                    ==
  ===============================================================
  -->
  <xs:element name="Detect_Datetime" type="xs:dateTime"/>
  <!--
  ===============================================================
  ==  Report_Datetime Class                                    ==
  ===============================================================
  -->
  <xs:element name="Report_Datetime" type="xs:dateTime"/>
  <!--
  ===============================================================
  ==  End_Datetime Class                                       ==
  ===============================================================
  -->
  <xs:element name="End_Datetime" type="xs:dateTime"/>

Zisiadis, et al. Experimental [Page 36] RFC 6137 NTTDM February 2011

  <!--
  ===============================================================
  ==  TT_Last_Update_Time Class                                ==
  ===============================================================
  -->
  <xs:element name="TT_Last_Update_Time" type="xs:dateTime"/>
  <!--
  ===============================================================
  ==  Time_Window_Start Class                                  ==
  ===============================================================
  -->
  <xs:element name="Time_Window_Start" type="xs:dateTime"/>
  <!--
  ===============================================================
  ==  Time_Window_End Class                                    ==
  ===============================================================
  -->
  <xs:element name="Time_Window_End" type="xs:dateTime"/>
  <!--
  ===============================================================
  ==  Work_Plan_Start_Datetime Class                           ==
  ===============================================================
  -->
  <xs:element name="Work_Plan_Start_Datetime" type="xs:dateTime"/>
  <!--
  ===============================================================
  ==  Work_Plan_End_Datetime Class                             ==
  ===============================================================
  -->
  <xs:element name="Work_Plan_End_Datetime" type="xs:dateTime"/>
  <!--
  ===============================================================
  ==  Related_External_Tickets Class                           ==
  ===============================================================
  -->
  <xs:element name="Related_External_Tickets"
              type="nttdm:eRelated_External_Tickets"/>

Zisiadis, et al. Experimental [Page 37] RFC 6137 NTTDM February 2011

  <!--
  ===============================================================
  ==  Additional_Data Class                                    ==
  ===============================================================
  -->
  <xs:element name="Additional_Data" type="xs:string"/>
  <!--
  ===============================================================
  ==  Related_Activity Class                                   ==
  ===============================================================
  -->
  <xs:element name="Related_Activity"
              type="nttdm:eRelated_Activity"/>
  <!--
  ===============================================================
  ==  History Class                                            ==
  ===============================================================
  -->
  <xs:element name="History" type="xs:string"/>
  <!--
  ===============================================================
  ==  Affected_Community Class                                 ==
  ===============================================================
  -->
  <xs:element name="Affected_Community" type="xs:string"/>
  <!--
  ===============================================================
  ==  Affected_Service Class                                   ==
  ===============================================================
  -->
  <xs:element name="Affected_Service" type="xs:string"/>
  <!--
  ===============================================================
  ==  Location Class                                           ==
  ===============================================================
  -->
  <xs:element name="Location" type="xs:string"/>

Zisiadis, et al. Experimental [Page 38] RFC 6137 NTTDM February 2011

  <!--
  ===============================================================
  ==  Network_Node Class                                       ==
  ===============================================================
  -->
  <xs:element name="Network_Node" type="nttdm:eNodes"/>
  <!--
  ===============================================================
  ==  Network_Link_Circuit Class                               ==
  ===============================================================
  -->
  <xs:element name="Network_Link_Circuit"
              type="nttdm:eNetwork_Link_Circuit"/>
  <!--
  ===============================================================
  ==  End_Line_Location_A Class                                ==
  ===============================================================
  -->
  <xs:element name="End_Line_Location_A" type="xs:string"/>
  <!--
  ===============================================================
  ==  End_Line_Location_B Class                                ==
  ===============================================================
  -->
  <xs:element name="End_Line_Location_B" type="xs:string"/>
  <!--
  ===============================================================
  ==  Open_Engineer Class                                      ==
  ===============================================================
  -->
  <xs:element name="Open_Engineer" type="xs:string"/>
  <!--
  ===============================================================
  ==  Contact_Engineers Class                                  ==
  ===============================================================
  -->
  <xs:element name="Contact_Engineers" type="nttdm:eEngineers"/>

Zisiadis, et al. Experimental [Page 39] RFC 6137 NTTDM February 2011

  <!--
  ===============================================================
  ==  Close_Engineer Class                                     ==
  ===============================================================
  -->
  <xs:element name="Close_Engineer" type="xs:string"/>
  <!--
  ===============================================================
  ==  Hash Class                                               ==
  ===============================================================
  -->
  <xs:element name="Hash" type="xs:string"/>
  <!--
  ===============================================================
  ==  Custom types definition                                  ==
  ===============================================================
  -->
  <xs:simpleType name="string_no_underscore">
   <xs:restriction base="xs:string">
    <xs:pattern value="[^_]*"/>
   </xs:restriction>
  </xs:simpleType>
  <xs:complexType name="eRelated_External_Tickets">
   <xs:sequence>
    <xs:element name="TTid" type="xs:string" minOccurs="0"
                maxOccurs="unbounded"/>
   </xs:sequence>
  </xs:complexType>
  <xs:complexType name="eRelated_Activity">
   <xs:sequence>
    <xs:element name="TT" type="xs:string" minOccurs="0"
                maxOccurs="unbounded"/>
   </xs:sequence>
  </xs:complexType>
  <xs:complexType name="eNodes">
   <xs:sequence>
    <xs:element name="Node" type="xs:string" minOccurs="0"
                maxOccurs="unbounded"/>
   </xs:sequence>
  </xs:complexType>

Zisiadis, et al. Experimental [Page 40] RFC 6137 NTTDM February 2011

  <xs:complexType name="eNetwork_Link_Circuit">
   <xs:sequence>
    <xs:element name="Link_Circuit" type="xs:string"
                 minOccurs="0" maxOccurs="unbounded"/>
   </xs:sequence>
  </xs:complexType>
  <xs:complexType name="eEngineers">
   <xs:sequence>
    <xs:element name="Engineer" type="xs:string" minOccurs="0"
                maxOccurs="unbounded"/>
   </xs:sequence>
  </xs:complexType>
  <xs:simpleType name="eTT_Type">
   <xs:restriction base="xs:string">
    <xs:enumeration value="Operational"/>
    <xs:enumeration value="Informational"/>
    <xs:enumeration value="Administrative"/>
    <xs:enumeration value="Test"/>
   </xs:restriction>
  </xs:simpleType>
  <xs:simpleType name="eType">
   <xs:restriction base="xs:string">
    <xs:enumeration value="Scheduled"/>
    <xs:enumeration value="Unscheduled"/>
   </xs:restriction>
  </xs:simpleType>
 <xs:simpleType name="eTT_Priority">
   <xs:restriction base="xs:string">
    <xs:enumeration value="Low"/>
    <xs:enumeration value="Medium"/>
    <xs:enumeration value="High"/>
   </xs:restriction>
  </xs:simpleType>

Zisiadis, et al. Experimental [Page 41] RFC 6137 NTTDM February 2011

  <xs:simpleType name="eTT_Short_Description">
   <xs:restriction base="xs:string">
    <xs:enumeration value="Core Line Fault"/>
    <xs:enumeration value="Access Line Fault"/>
    <xs:enumeration value="Degraded Service"/>
    <xs:enumeration value="Router Hardware Fault"/>
    <xs:enumeration value="Router Software Fault"/>
    <xs:enumeration value="Routing Problem"/>
    <xs:enumeration value="Undefined Problem"/>
    <xs:enumeration value="Network Congestion"/>
    <xs:enumeration value="Client Upgrade"/>
    <xs:enumeration value="IPv6"/>
    <xs:enumeration value="QoS"/>
    <xs:enumeration value="VoIP"/>
    <xs:enumeration value="Other"/>
   </xs:restriction>
  </xs:simpleType>
  <xs:simpleType name="eTT_Impact_Assessment">
   <xs:restriction base="xs:string">
    <xs:enumeration value="No impact"/>
    <xs:enumeration value="Reduced redundancy"/>
    <xs:enumeration value="Minor performance impact"/>
    <xs:enumeration value="Severe performance impact"/>
    <xs:enumeration value="No connectivity"/>
    <xs:enumeration value="On backup"/>
    <xs:enumeration value="At risk"/>
    <xs:enumeration value="Unknown"/>
   </xs:restriction>
  </xs:simpleType>
  <xs:simpleType name="eTT_Status">
   <xs:restriction base="xs:string">
    <xs:enumeration value="Opened"/>
    <xs:enumeration value="Updated"/>
    <xs:enumeration value="Closed"/>
    <xs:enumeration value="Solved"/>
    <xs:enumeration value="Opened/Closed"/>
    <xs:enumeration value="Inactive"/>
    <xs:enumeration value="Cancelled"/>
    <xs:enumeration value="Reopened"/>
    <xs:enumeration value="Superseded"/>
   </xs:restriction>
  </xs:simpleType>

Zisiadis, et al. Experimental [Page 42] RFC 6137 NTTDM February 2011

  <xs:simpleType name="eTT_Source">
   <xs:restriction base="xs:string">
    <xs:enumeration value="Users"/>
    <xs:enumeration value="Monitoring"/>
    <xs:enumeration value="Other NOC"/>
   </xs:restriction>
  </xs:simpleType>
 </xs:schema>

7. Security Considerations

 The NTTDM data model defines a data model and the relevant XML Schema
 for trouble ticket normalization; as such, the NTTDM itself does not
 raise any security concerns.  However, some security issues SHOULD be
 considered as network TTs could carry sensitive information (IP
 addresses, contact details, authentication details, commercial
 providers involved, etc.) about flagship institutions (military,
 health centre...).
 The security considerations MAY involve measures during the exchange
 as well as during processing of the information.
 The HASH field is intended to provide an integrity insurance
 attribute within the exchanged tickets; however, it alone does not
 ensure integrity.
 Confidentiality MAY be ensured by encrypting whole tickets or only
 some parts of them.  This could permit meaningful tickets to be
 disclosed, while only sensitive information would be protected.
 Peer entity authentication SHOULD be provided in order to establish a
 session with data origin authentication, regardless of the form in
 which the TTs are exchanged -- being delivered either through email,
 web forms, or through a Simple Object Access Protocol (SOAP) service.
 SOAP is considered the better choice; the model itself, though, does
 not specify the communications requirements.
 The underlying communications service MUST provide guarantees to
 properly address integrity, confidentiality, and peer entity
 authentication.  The selection of the enforcing mechanisms is not in
 the scope of this document, and the choice is up to the implementers.
 For data processing security, each participating organization MAY use
 its own privacy policy, as part of its own data processing system.
 This approach avoids any interoperability issues and does not pose
 any extra burden for the adoption of the current scheme into the
 operational procedures of the NOCs.  Unauthorized and inappropriate
 usage MUST be avoided.

Zisiadis, et al. Experimental [Page 43] RFC 6137 NTTDM February 2011

8. IANA Considerations

 This document uses URNs to describe an XML namespace and Schema
 conforming to a registry mechanism described in [7].
 Registration for the NTTDM namespace:
 o  URI: urn:ietf:params:xml:ns:nttdm-1.0
 o  Registrant Contact: See the first author listed in the "Authors'
    Addresses" section of this document.
 o  XML: None.  Namespace URIs do not represent an XML specification.
 Registration for the NTTDM XML Schema:
 o  URI: urn:ietf:params:xml:schema:nttdm-1.0
 o  Registrant Contact: See the first author listed in the "Authors'
    Addresses" section of this document.
 o  XML: See the XML Schema in Section 6 of this document.

9. Contributors

 Leandros Tassiulas
 Centre for Research and Technology Hellas
 6th km Thermi-Thessaloniki, 57001
 Hellas
 EMail: leandros@uth.gr
 Chrysostomos Tziouvaras
 Greek Research and Technology Network
 56, Mesogion Av. 11527, Athens
 Hellas
 EMail: tziou@grnet.gr
 Xavier Jeannin
 National Centre for Scientific Research
 Network Unit - UREC
 France
 EMail: Xavier.Jeannin@urec.cnrs.fr

Zisiadis, et al. Experimental [Page 44] RFC 6137 NTTDM February 2011

10. Acknowledgements

 The following groups and individuals contributed substantially to
 this document and are gratefully acknowledged:
  1. Toby Rodwell and Emma Apted (DANTE)
  1. Claudio Allocchio, Gloria Vuagnin, and Claudia Battista (GARR)
  1. Karin Schauerhammer and Robert Stoy (DFN)

11. References

11.1. Normative References

 [1]   Bradner, S., "Key words for use in RFCs to Indicate Requirement
       Levels", BCP 14, RFC 2119, March 1997.
 [2]   World Wide Web Consortium, "Extensible Markup Language
       (XML) 1.0 (Fifth Edition)", W3C Recommendation, 26 November
       2008, <http://www.w3.org/TR/2008/REC-xml-20081126>.
 [3]   World Wide Web Consortium, "XML Schema Part 0: Primer Second
       Edition", W3C Recommendation, 28 October 2004,
       <http://www.w3.org/TR/2004/REC-xmlschema-0-20041028/>.
 [4]   World Wide Web Consortium, "XML Schema Part 1: Structures
       Second Edition", W3C Recommendation, 28 October 2004,
       <http://www.w3.org/TR/xmlschema-1/>.
 [5]   World Wide Web Consortium, "XML Schema Part 2: Datatypes Second
       Edition", W3C Recommendation, 28 October 2004,
       <http://www.w3.org/TR/xmlschema-2/>.
 [6]   World Wide Web Consortium, "Namespaces in XML 1.0 (Third
       Edition)", W3C Recommendation, 8 December 2009,
       <http://www.w3.org/TR/2009/REC-xml-names-20091208/>.
 [7]   Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688,
       January 2004.

11.2. Informative References

 [8]   Enabling Grids for E-sciencE, http://www.eu-egee.org/.
 [9]   Enabling Grids for E-sciencE, "ENOC, EGEE Network Operation
       Centre", http://technical.eu-egee.org/index.php?id=353.

Zisiadis, et al. Experimental [Page 45] RFC 6137 NTTDM February 2011

 [10]  Rumbaugh, J., Jacobson, I., and G. Booch, "The Unified Modeling
       Language Reference Manual," ISBN 020130998X, Addison-Wesley,
       1998.
 [11]  Johnson, D., "NOC Internal Integrated Trouble Ticket System
       Functional Specification Wishlist ("NOC TT REQUIREMENTS")",
       RFC 1297, January 1992.

Authors' Addresses

 Dimitris Zisiadis (editor)
 Centre for Research and Technology Hellas
 6th km Thermi-Thessaloniki, 57001
 Hellas
 EMail: dzisiadis@iti.gr
 Spyros Kopsidas (editor)
 Centre for Research and Technology Hellas
 6th km Thermi-Thessaloniki, 57001
 Hellas
 EMail: spyros@uth.gr
 Matina Tsavli (editor)
 Centre for Research and Technology Hellas
 6th km Thermi-Thessaloniki, 57001
 Hellas
 EMail: sttsavli@uth.gr
 Guillaume Cessieux (editor)
 Computer Centre of National Institute for
 Nuclear Physics and Particle Physics (IN2P3-CC)
 France
 EMail: Guillaume.Cessieux@cc.in2p3.fr

Zisiadis, et al. Experimental [Page 46]

/data/webs/external/dokuwiki/data/pages/rfc/rfc6137.txt · Last modified: 2011/02/19 02:16 (external edit)