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Network Working Group RARE WG-MSG Task Force 88 Request for Comments: 1616 May 1994 RARE Technical Report: 10 Category: Informational

   X.400(1988) for the Academic and Research Community in Europe
          A report by the RARE Task Force on X.400(1988)
           of the RARE Working Group on Mail & Messaging

Status of this Memo

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

1. Abstract

 The European research and development community, as represented by
 the member research networks of RARE, has lead the deployment within
 the global R&D community of X.400 electronic messaging services, as
 specified in the international recommendations CCITT X.400(1984), for
 more than five years. As a result of providing such services to the
 European R&D users it has become clear that there is an existing and
 ever increasing demand from these users for new and enhanced
 electronic messaging services and product to be used to communicate
 within the R&D community but within commercial service providers and
 organisations as well.
 It is also clear that new services, such as Multimedia messaging and
 Secure messaging, and the resulting products promise dramatic
 benefits and opportunities, for not only the R&D community but also
 for the wider commercial, industrial and public communities, in terms
 of facilitating innovative ways of working and living which can only
 enhance the missions and goals of the respective communities. Not
 least the establishment of globally pervasive messaging services
 between all users, R&D and commercial, is facilitated by the early
 adoption of such advanced new services. An indication of the
 importance of such a messaging service can be appreciated if one
 considers that in many organizations (especially commercially based)
 messaging may be the only method to communicate between independent
 organizations due to security considerations and lower layer network
 differences.
 The Commission of European Communities (CEC) VALUE subprogram II has
 been established to support initiatives relating to the development
 and adaptation of R&D networks in member states.  Amongst other

RARE WG-MSG Task Force 88 [Page 1] RFC 1616 X.400(88) for European Academics and Research May 1994

 initiatives the VALUE program supports X.400 initiatives in certain
 countries. VALUE support has so far been limited to X.400(1984)
 initiatives, as X.400(1984) has up until now been the dominating OSI
 services. However as X.400(1988) implementations have started to
 appear a VALUE funded study of the X.400(1988) aspects of messaging
 and their impact on the R&D community was felt necessary. This report
 is one of the results of that study.
 The report documents the results of a task force on X.400(1988)
 deployment of the RARE Mails and Messaging Work Group during the
 period from November 1992 until October 1993. Open reviews of the
 report have occurred in the RARE Mail and Messaging Work Group and
 within the IETF X.400ops Working Group.
 The scope of the report is limited to deployment of X.400(1988)
 services, and as such the report does not contain any recommendations
 on development and deployment of Internet RFC 822 / MIME/ PEM related
 (pilot) services. However, since the report shows that both
 X.400(1988) and RFC 822 / MIME / PEM will be developed and used
 within the European R&D community, such a pilot should also
 considered.  Note: RFC 822 is also known as Internet STD 11.
 Circulation of this report is unlimited. Comments on this report may
 be sent to the e-mail distribution list:
  RFC 822: wg-msg@rare.nl
  X.400:   S=wg-msg;O=rare;P=surf;A=400net;C=nl;

Task Force Members:

  Claudio Allocchio (INFN),
  Harald T. Alvestrand (SINTEF),
  James C. I. Craigie (JNT),
  Urs Eppenberger (SWITCH),
  Frode Hernes (maXware),
  Jeroen Houttuin (RARE),
  Erik Huizer (SURFnet) - chairman,
  Steve Kille (ISODE Consortium),
  James A. (Jim) Romaguera (NetConsult).
  Editors: James A. (Jim) Romaguera & Erik Huizer
 The work of this Task Force has been funded by the Commission of
 European Communities (CEC) VALUE subprogram II, Stichting SURF and
 SURFnet bv.

RARE WG-MSG Task Force 88 [Page 2] RFC 1616 X.400(88) for European Academics and Research May 1994

Table of Contents

 1.  Abstract                                                      1
 2.  Management Summary                                            3
 3.  Framework for the report                                      6
 4.  Present situation of European Messaging                       7
    4.1. Messaging services                                        7
    4.2. Requirements for messaging                                8
           4.2.1. User Oriented                                    9
           4.2.2. Service provider viewpoint                      10
    4.3. Messaging capabilities                                   11
 5.  Possible solutions for providing globally pervasive
     messaging                                                    12
    5.1. PC LAN E-mail systems                                    13
    5.2. RFC 822, MIME and PEM services                           15
    5.3. X.400 - 1984 and 1988                                    19
 6.  Migration to X.400(1988)                                     23
    6.1. PC LAN E-mail systems                                    25
    6.2. RFC 822, MIME and PEM services                           25
    6.3. X.400(1984) services                                     27
    6.4. Mail-11 services                                         28
 7.  Benefits of migrating to X.400(1988) and the involved costs  28
 8.  Main Recommendations                                         33
 9.  Security Considerations                                      34
 10. Reading List and Bibliography                                35
 11. Terminology                                                  37
 Appendix A - Elaboration on the main recommendations             38
 Appendix B - A number of detailed guidelines.                    40
 Authors' Addresses                                               44

2. Management Summary

 This document reports the results of study of the X.400(1988) aspects
 of messaging and their impact on the R&D community. The study was
 funded by the CEC under VALUE Subprogram II and has been carried out
 by a task force on the RARE Mail Working Group.  The document is
 targeted at technical decision makers as well as those who would fund
 activity in this area.
 The document presents the existing situation as regards the
 predominate messaging technologies within Europe. These are presented
 within the context of a number of large messaging communities that
 are using these technologies:
  1. RFC 822,
  2. X.400(1984),
  3. Mail-11 and
  4. PC LAN messaging

RARE WG-MSG Task Force 88 [Page 3] RFC 1616 X.400(88) for European Academics and Research May 1994

 Three major European communities are referenced:
  1. Commercial service providers
  2. R&D community
  3. Commercial organisations using messaging services.
 The report states the following facts:
  1. The resources, human or financial, to operate multiple wide

area messaging services connecting together independent

    organisations are high. As such it is desirable to try and
    keep to a minimum the number of such services. This statement
    is true for the R&D community but is also highly likely to be
    valid for the general European industry.
  1. There are two publicly available technological standards

that can be used by open communities, such as the R&D

    community and public service providers: the X.400(1984 and
    1988) recommendations and the Internet RFC 822 / MIME / PEM
    standards.
  1. There is an established very large global user base of

Internet RFC 822 and X.400(1984) messaging services. Both

    services have their own momentum within different parts of
    the user community, both are still developing and growing
    fast.
 The report concludes that X.400(1988) will be the preferred protocol
 for inter organizational connection for European industry and
 government and parts of the European R&D community.  RFC 822 / MIME /
 PEM will be the preferred protocol suite for inter-organisational
 connection for the Internet community and, as products are already
 widely available, it is the preferred protocol for parts of the
 European R&D community.
 The goal of European pervasive messaging - incorporating Industry,
 Government and Academia - would be best accommodated and reached by
 the establishment of a single messaging service.  However taking the
 above into account, this is not feasible, as X.400(84 and 88) and RFC
 822( and MIME) based services will be around for a long time to come.
 To increase the functionality of Wide Area E-mail services there is a
 clear necessity to:
  1. migrate RFC 822 services to a RFC 822 / MIME / PEM service.

A MIME based service offers more functionality to the user

    than a plain RFC 822 service.
  1. migrate existing X.400 services to a X.400(1988) service.

RARE WG-MSG Task Force 88 [Page 4] RFC 1616 X.400(88) for European Academics and Research May 1994

    Due to the lack of scalability of the X.400(1984) service in
    terms of extra functionality, it will become increasingly
    difficult to meet the needs of research users of existing
    X.400(1984) services unless an X.400(1988) service is put
    into place.
  1. provide a transparent gateway between X.400(1988) and RFC

822/MIME/PEM. For the European R&D community it is essential

    to have a transparent gateway between the X.400(1988) service
    and the RFC 822 / MIME / PEM service, thus ensuring
    connectivity between these two services with a maximum
    functionality.
 Such a gateway is technically feasible and it is an essential part of
 an unified E-mail service. Without such a standardised gateway the
 overall E-mail service would deteriorate.
 The lack of open standards for the PC LAN messaging systems
 discourages their use as 'backbone' messaging technologies within
 open communities. However the products that these systems deliver to
 end users ensures that their already large share of the messaging
 market will continue to exist for some time. Thus it is also
 essential that strategies that allow these systems to be 'seamlessly'
 integrated within the global messaging community are put in place.
 Not least due to the indications that the main messaging vendors are
 developing X.400(1988) and RFC 822/MIME gateways, a strategy to link
 these systems together via X.400 and RFC 822 should be developed.
 The report concludes with a set of recommendations, the main one
 being the establishment of a X.400(1988) European pilot messaging
 service for the R&D community. This pilot should include the
 establishment of a transparent gateway service between X.400(1988)
 and RFC 822/MIME. The goal of a European pilot is to ensure the
 successful deployment of a European wide operational X.400(1988)
 service that is pervasive and meets the needs of users. By collecting
 together the issues related to the establishment of a European
 X.400(1988) service, this report acts as a focal point and stimulant
 for discussion on this topic within the R&D community. In the report
 a summary of the benefits and problems of each of the above messaging
 technologies within the context of achieving a global messaging
 service, of which the R&D community is one part, is presented.
 Further the document identifies issues, strategies and
 recommendations related to the migration and coexistence of these
 technologies within the scope of mainly the European R&D community
 but also in relation to other messaging communities. A cost / benefit
 analysis on the establishment of a European wide pilot X.400(1988)
 messaging service is also presented. Finally a reading list of
 references related to this subject has been compiled.

RARE WG-MSG Task Force 88 [Page 5] RFC 1616 X.400(88) for European Academics and Research May 1994

 The report does not include any recommendations on development and
 deployment of RFC 822 / MIME / PEM related (pilot) services, as these
 are outside of the scope of the Task Force. However, since the report
 shows that both X.400(1988) and RFC 822 / MIME / PEM will be
 developed and used within the European R&D community, such a pilot
 should also be considered.

3. Framework for the report

 With the belief that user demands for new messaging services such as
 Multimedia and Secure Messaging would develop, the RARE community
 (together with other communities; most notably the Internet
 Engineering Task Force (IETF)) has over the preceding years
 experimented in new messaging and related technologies.  Experiments
 and pilots, have been performed in messaging services e.g., as
 recommended by CCITT X.400(1988) and Directory Services based upon
 the CCITT X.500(1988) recommendations.
 The results of such pilots and experiments indicate that it is now
 opportune to commence a pilot X.400(1988) messaging service for the
 European R&D community. The major goals of the pilot being, to
  1. establish a large scale European wide pilot messaging

service based on X.400(1988).

  1. collaborate with and facilitate the commencement of similar

pilot services within diverse communities; both R&D and non-

    R&D (e.g., commercial ADMDs and PRMDs, etc.); both European
    and non-European (e.g., North American , Asian, etc.).
  1. encourage and assist the development and deployment of a

wide variety of commercial and public domain X.400(1988)

    messaging products that meet the user's needs, for instance
    X.400(1988) products such as User Agents (UAs), Message
    Stores (MSs), Message Transfer Agents (MTAs) and gateways
    between X.400(1988) services and other widespread messaging
    services i.e., RFC 822, Mail-11 and proprietary.
  1. prove that such a service and products efficiently meets the

existing and expected demands for new messaging services by

    European R&D users. And as such determine the steps for a
    European deployment of an operational X.400(1988) messaging
    service.
  1. determine the needed steps to facilitate migration for the

existing operational R&D X.400(1984) based messaging service,

    as represented by the R&D MHS service (the former COSINE
    MHS), RFC 822 / MIME / PEM based messaging services and the

RARE WG-MSG Task Force 88 [Page 6] RFC 1616 X.400(88) for European Academics and Research May 1994

    HEPnet / SPAN Mail-11 based messaging service to an
    operational X.400(1988) messaging service. It is self evident
    that during such migrations, transition steps must be
    included that allow a period of coexistence, at the highest
    possible service level, between X.400(1988), X.400(1984), RFC
    822 / MIME and HEPnet / SPAN Mail-11 services.
  1. determine the needed steps that allow proprietary messaging

systems, that are widely deployed within the European R&D

    community to be integrated at as high as possible service
    level, by an X.400(1988) infrastructure.
 This report identifies the issues involved in such a pilot service.
 It is not a concrete proposal for such a project but the report
 discusses advantages and disadvantages, costs and enefits and
 migration issues for deploying a X.400(1988) service. As such it is a
 discussion and feasibility paper on the creation of a large scale
 European wide pilot X.400(1988) messaging service for the European
 R&D community.

4. Present situation of European Messaging

4.1. Messaging services

 Electronic messaging within Europe can be viewed as a number of
 messaging services communities. Three important communities comprise,
  1. Commercial e-mail networks,
  2. Research e-mail networks and
  3. PC LAN messaging systems.
 Commercial e-mail networks are classified as either ADMDs or PRMDs.
 ADMDs and PRMDs are operating in nearly every European country.
  1. ADMD services (or public commercial e-mail services) are

provided by over 50 service providers which have

    interconnected using the X.400(1984) protocols. The topology
    between these ADMDs, although not yet 'mesh', can be stated
    as progressing quite rapidly to this optimum goal. However
    there is still a way to go before ADMDs provide full European
    connectivity.
  1. PRMDs (or private commercial e-mail service providers) have

interconnected to ADMDs and other PRMDs predominantly using

    the X.400(1984) protocols but also with proprietary
    protocols.

RARE WG-MSG Task Force 88 [Page 7] RFC 1616 X.400(88) for European Academics and Research May 1994

 Research networks are providing messaging services in every European
 country. These R&D service providers are operated as either ADMDs or
 PRMDs and are using both X.400(1984) protocols and Internet RFC 822
 protocols to connect to each other.
 Moreover, there are also large R&D communities (i.e., HEPnet and
 SPAN) using proprietary protocols (i.e., DECnet Phase IV and Mail-11)
 as their main messaging systems. The DECnet IV based communities are
 now migrating to DECnet Phase V (OSI connectionless protocol stack),
 which provides X.400(1988) (plus X.400(1984)) as a major messaging
 system.  In general, all these services are totally interconnected.
 As such it is a statement of fact that there exists within the
 European R&D community, two parallel interconnected messaging
 infrastructures based upon X.400(1984) and RFC 822. However
 interconnections between the R&D messaging community and the majority
 of the European commercial service providers use the X.400(1984)
 protocols.
 It is also clear that the commercial world mostly makes inter-
 organizational messaging interconnections using the X.400(1984)
 protocols. And also that the commercial messaging world is not as
 totally interconnected as the R&D messaging community.  Finally, for
 a number of commercial and public organisations there is often a
 mandatory requirement to use X.400 for messaging interconnections.
 The usage of PC LAN messaging systems is increasing very rapidly
 within the academic and commercial communities. In general, PC LAN
 messaging services within both communities do not use X.400(1984) or
 RFC 822 messaging systems but systems based upon proprietary
 protocols. The PC LAN messaging systems can be considered more as
 'Islands of Messaging' that gateway to the commercial and R&D
 messaging services by using X.400(1984) or RFC 822 gateways. PC LAN
 messaging systems within commercial organisations connect to
 commercial service providers also via proprietary protocols. The PC
 LAN messaging services, although probably comprising the largest
 number of users, are in general poorly integrated with the global
 messaging service (The Dutch, UK and Italian academic communities
 confirm that there appears to be many such 'Islands' of PC LAN
 messaging systems within their networks.).

4.2. Requirements for messaging

 Experience with existing global e-mail services has proven that with
 the increased use of messaging, there follows an awareness of extra
 requirements for related services. These requirements can be
 classified into 'User based Requirements' and 'Service Provider based
 Requirements' to either support, or exploit, high quality messaging
 services. These requirements are elaborated upon within this chapter.

RARE WG-MSG Task Force 88 [Page 8] RFC 1616 X.400(88) for European Academics and Research May 1994

4.2.1. User Oriented

 The only thing a user requires is an easy to use, well integrated,
 user interface to electronic mail. Usually the user does not care
 what protocol is used. However there are certain inherent
 requirements to the functionality that can be identified as user
 requirements. The main user requirements identified are:
  1. Distribution Lists (DLs)
    A widely perceived omission from the X.400(1984) recommendations
    was the lack of support of DLs. Distribution lists allow users to
    enlist themselves onto electronic mail expander lists
    (distribution lists). A message to such a distribution list will
    automatically, and without significant delay, be sent on to anyone
    whose electronic mail address is on that list. Such a list can be
    a public list, that is meant for discussions on a specific
    subject, much like a sort of "magazine". However the list can also
    be a "closed" list, containing only a selected set of people who
    need to communicate privately, e.g., a project-team.
  1. Multinational language and Multimedia support
    European users have for many years been frustrated in their
    inability to use their national character sets when communicating
    using messaging systems. The problems within e-mail systems that
    were causing this character set frustration are at their base the
    same problem that would get in the way of Multimedia messaging
    like:
  1. lack of binary data support
  2. lack of standardised encoding schema's
  3. definition of multiple body-parts
    The enormous potential of Multimedia systems and services
    (especially within the commercial community as evidenced by the
    enormous press publicity and mega-mergers positioning companies to
    exploit this technology but also within the government spheres
    i.e., the U.S.A. Government's 'Information Superhighway'
    initiative) has acted as a spur to make rapid progress in solving
    the problems in this area.
  1. White pages Directory Service
    A white pages directory service provides a unique but very basic
    and important service; a way to store and find information about
    people and resources that is analogous to a telephone service's
    paper based directory i.e., White Pages. User's E-mail addresses

RARE WG-MSG Task Force 88 [Page 9] RFC 1616 X.400(88) for European Academics and Research May 1994

    can be stored for subsequent retrieval by E-mail systems.
  1. EDI
    EDI today is not extensively used within the academic environment.
    However there is a distinct potential within the academic
    community to reduce costs and improve services with EDI. Potential
    EDI uses could be,
  1. EDI between universities
  2. EDI between universities and government
  3. EDI between universities and lower level educational

institutions (e.g., student records)

  1. Commercial EDI using the Internet as an infrastructure.
    The significance of maintaining end to end integrity (especially
    security aspects) of the EDI messages mandates that no gateways
    should be used between originator and recipient.
  1. Support of Security services
    E-mail as it is currently used is far from secure. To allow for
    serious usage of E-mail security issues need to be addressed,
    like:
  1. integrity; making sure that the message is transferred

intact, without any changes or additions.

  1. encryption; making sure the message content is only

decipherable by the intended recipient.

  1. authentication; making sure that the originator and/or

recipient are authenticated.

4.2.2. Service provider viewpoint

 The task force believes the following points as being the most
 significant service provider requirements:
  1. Network Management
    This area is still very new, in terms of offering standardised
    protocols, services and products for management. However a minimum
    'goal' is to provide for central management functions that will
    allow providers to offer a better quality of service.  There is
    presently ongoing work within the IETF Working Group MADMAN to
    define SNMP monitoring and managing of E-mail systems, gateways
    and X.500 directory systems. A number of management areas that
    need to be worked upon include: QOS, Service Level Agreements
    (SLAs), Multiple system queue management, Accounting, Routing Co-

RARE WG-MSG Task Force 88 [Page 10] RFC 1616 X.400(88) for European Academics and Research May 1994

    ordination and Message Tracing.
  1. Support of MTA routing
    Dynamic routing from MTA to MTA, relieves the necessity to
    maintain large routing tables, especially within a large PRMD, or
    community of PRMDs (like the R&D MHS community).
  1. Address mapping between RFC 822 and X.400
    The widespread use of X.500 or DNS for mapping, allows a reduction
    of manpower for centrally co-ordinating globally consistent
    X.400-to-RFC-822 mapping tables and distributes the responsibility
    for updating the mapping rules. This should allow mapping rules to
    change when needed and to be available immediately.
  1. UA capabilities registration
    The use of the directory to register UA capabilities for
    X.400(1988), X.400(1984) and RFC 822 / MIME / PEM systems is a
    very desirable benefit for users in terms of speeding the
    deployment of new messaging services (e.g., Multimedia Messaging).

4.3. Messaging capabilities

 Due to the problems of gatewaying within a multi-protocol messaging
 environment, the great majority of R&D E-mail users are reduced to
 using only InterPersonal Messaging (IPM) services based upon the
 exchange of message body parts using CCITT character set IA5 (US
 ASCII).
 Within the R&D community recent work to meet user requirements for
 non ASCII messaging services - as documented above - has resulted in
 enhancements to the messaging services based upon RFC 822 protocols.
 The enhancements provide Multimedia support via the Multipurpose
 Internet Mail Extensions (MIME) and the prospect in the very near
 future of secure messaging via Privacy Enhanced Mail (PEM).
 Deployment of the MIME enhanced RFC 822 based services, via
 distribution of software and the setting up of the needed
 organisational structures, has commenced. The PEM enhancements are in
 a large scale pilot phase e.g., VALUE PASSWORD project.
 In the case of X.400(1984) the usage of non ASCII body parts is
 mostly effected by bilateral agreement between recipient and
 originator, through use of body part 14. In practice this restricts
 the exchange of non ASCII body parts to those cases where the
 recipient and the originator use the same bilateral agreement or else
 the originator includes an ASCII message explaining the included

RARE WG-MSG Task Force 88 [Page 11] RFC 1616 X.400(88) for European Academics and Research May 1994

 content type. Besides IPM there is a growing usage of EDI on top of
 X.400(1984).
 With the above X.400(1984) deficiencies in mind, X.400(1988) has been
 specified by the CCITT / ISO to meet new user demands.  X.400(1988)
 provides support for various different body parts, enhanced security
 features, international character set support capabilities and
 support of X.500 Directory Services. Due to the technological
 potential of these standards to satisfy user needs for new messaging
 services, the R&D community has been experimenting and piloting
 X.400(1988) and X.500(1988) services.  As there is a strong
 dependency of X.400(1988) messaging upon X.500(1988) directory
 services, the necessary precondition to supply these user demands is
 a deployed and operational X.500(1988) directory service. Piloting
 and deployment of the X.500(1988) directory service within the R&D
 community has been successfully initiated and co-ordinated by the
 COSINE and the VALUE PARADISE projects.
 Similarly, secure messaging has been addressed by the VALUE PASSWORD
 project and the RARE and IETF communities. Work to solve problems
 related to directory support of X.400(1988) messaging has been
 pursued within the IETF and RARE. The relevant RARE and IETF work
 groups (e.g., RARE WG-MSG, IETF MHS-DS, etc.) have also worked to
 produce any needed enhancements to the base X.400(1988) and
 X.500(1988) standards.  Last but not least it should not be
 overlooked that X.400(1988), as compared to X.400(1984), provides a
 comprehensive basis for gatewaying to and from RFC 822 / MIME / PEM
 and PC LAN messaging services. To that respect the IETF has defined
 standards for gatewaying Multimedia mail between RFC 822 / MIME / PEM
 and X.400(1988). As RFC 822 / MIME / PEM is now being deployed on the
 Internet, deployment of X.400(1988) services is needed to assure
 multimedia and secure messaging connectivity for the European R&D
 community.

5. Possible solutions for providing globally pervasive messaging

 As can be now seen, a correlation of the present situation to the
 requirements of the user, shows that the current messaging services
 do not match the needs of users. To try to meet these needs a number
 of developments within various messaging technology areas are
 occurring. The following messaging technological areas, due to the
 present installed user base within the R&D community, are considered
 relevant:
  1. PC LAN E-mail systems such as Lotus cc:Mail, Microsoft Mail

and Novell MHS

  1. RFC 822 / MIME / PEM E-mail services
  2. X.400(1988) messaging services

RARE WG-MSG Task Force 88 [Page 12] RFC 1616 X.400(88) for European Academics and Research May 1994

 Ongoing developments within each of the above technological areas
 provide new messaging options for the R&D community. The ability of
 each technological area to provide solutions for user and service
 provider requirements is summarised within this chapter.

5.1. PC LAN E-mail systems

 Currently the usage of PC LAN E-mail systems is mostly for internal
 communication within an organisation. External connections, if
 present at all, to public service providers or other organisations is
 mostly through gateways to X.400(1984) or RFC 822. The use of a PC
 LAN E-mail system in terms of an infrastructure for interconnecting
 E-mail systems of different hues is not common within the Research
 community.  Recent experience, from amongst others the Dutch Research
 network - SURFnet - [14] and the Norwegian Directorate for Public
 Management - Statskonsult - [18], has shown that a number of problems
 (i.e., limited functionality, high operational management cost, etc.)
 can be expected should these PC LAN E-mail systems be used as an E-
 mail infrastructure. (The use of native X.400 protocols for PC LAN
 E-mail systems would avoid the usage of gateways and would thus
 alleviate many of these problems.) A summary of those problems and
 some relevant issues follows:
  1. Interconnecting heterogeneous PC LAN messaging systems
    One very distinct benefit for E-mail users of all hues is the
    potential to integrate heterogeneous PC LAN messaging systems with
    a minimum loss of service (e.g., multimedia services) by
    connecting them via X.400(1988) (or RFC 822/MIME/SMTP).
    X.400(1988) is already being used, or under active development,
    for connecting together PC LAN messaging systems in a number of
    environments (e.g., Apple Macintoshes, DEC, Microsoft, Lotus,
    etc.). This tendency to gateway PC LAN messaging systems via
    X.400(1988) will increase and is one of the benefits that
    X.400(1988) brings to global multiprotocol messaging.
  1. Multimedia and binary data support
    The benefit of E-mail systems using these PC LAN systems is that
    the user interfaces are usually well integrated in the users
    standard working environment. Using a proprietary protocol these
    systems allow not only text (ASCII) but also binary, word
    processor, video, audio and other types of files to be
    transported. To reap the benefits of this multimedia / binary data
    transfer it would normally require that the same type of gateway
    is used by sender and receiver. Transporting these same files to
    another type of PC LAN E-mail system is not possible through the

RARE WG-MSG Task Force 88 [Page 13] RFC 1616 X.400(88) for European Academics and Research May 1994

    current gateways without some information loss. In effect PC LAN
    E-mail system's X.400 (or RFC 822) gateways from different vendors
    perform acceptably only for text body parts.  True heterogeneous
    multimedia PC LAN messaging needs gateways to X.400(1988)'s
    service.
  1. Application Programming Interfaces
    To help solve the problem of portability for Mail Enabled
    Applications Microsoft, Lotus, Novell, XAPIA and X/OPEN have been
    working on a number of standards for the Application Interface to
    mail transport protocols (i.e., Mail Application Programming
    Interface - MAPI, Vendor Independent Messaging - VIM, Common Mail
    Calls - CMC). These efforts are structured independent of the
    existing 'Wide-Area' or inter organisational E-mail protocols of
    X.400(1984) and RFC 822. However the MAPI, VIM and CMC efforts,
    due to their proposers (respectively Microsoft, Lotus and X/OPEN),
    do look like they will provide the stimulant to various software
    developers to develop more portable applications plus allow the
    rich functionality of X.400(1988) to be accessed by these
    applications thus reducing the need for gatewaying to X.400(1988).
  1. Security
    As the PC LAN E-mail systems require gateways for connectivity,
    they pose a problem with regard to encrypted messages.  Gatewaying
    of secure messages is normally not possible. The gatewaying of
    secure messages is a general problem of gatewaying from one mail
    system to any other system and is not specific to PC LAN E-mail
    systems.
  1. Directory Services
    To date mostly proprietary directory services have been deployed
    that do not match the needs of the users in terms of access
    controls for data, distributed and decentralised across
    organisations. X.500 based services promise solutions to such
    needs. As a result various suppliers have announced support of
    X.500 directory services for their E-mail products. However,
    should these interfaces be delayed then support of an inter
    organisational 'White Pages' services requires either,
  1. directory information exchange products (i.e., directory

gateways) deployed between a proprietary system and an X.500

      directory system

RARE WG-MSG Task Force 88 [Page 14] RFC 1616 X.400(88) for European Academics and Research May 1994

  1. gateways between de-facto market based proprietary

standards, such as Retix Directory Exchange (DX) or

      Soft*switch's Directory Synchronisation (DS), and X.500
      protocols
  1. duplicated directories i.e., one proprietary and one X.500

need to be operated.

 It should be stressed that gatewaying mechanisms and products are
 often problematic due to the lack of an open standard on the
 proprietary messaging system and or directory system. (As an aside it
 is thus essential to establish an operational X.500 infrastructure,
 including E-mail user interfaces that can transparently access this
 Directory Service, as soon as possible.)

5.2. RFC 822, MIME and PEM services

 RFC 822 messaging services are widely deployed within the R&D
 community. There is ongoing work to extend RFC 822 to meet user
 requirements. Some of these extensions are elaborated upon within
 this chapter.
  1. Distribution lists
    RFC 822 allows for the usage of DLs. Management of DLs is not
    (yet) standardised.
  1. RFC 822 multimedia messaging via MIME
    With the arrival of MIME, the RFC 822 service has an additional
    protocol standard that addresses Multimedia messaging very
    comprehensively. In terms of user needs, MIME now allows messaging
    body parts to comprise multinational character sets and binary
    data. Multi-body part messages are also supported.  One of MIME's
    real strengths, in terms of deployment within the existing RFC 822
    service, is that it achieves its goals by overlaying its services
    over the existing RFC 822 service and thus mandating no changes to
    the in place RFC 822 infrastructure. This greatly simplifies the
    MIME deployment.
  1. RFC 822 secure messaging via PEM
    Just as MIME has brought multimedia messaging to RFC 822 services,
    Privacy Enhanced Mail (PEM) is bringing secure messaging to RFC
    822 services. PEM also has used the same approach as MIME to
    deploy secure messaging within RFC 822 services; overlay PEM
    services over the existing RFC 822 services without requiring
    changes to the RFC 822 infrastructure. PEM brings confidentiality

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    and integrity of messages to RFC 822 users. However a number of
    problems with PEM, and X.400(1988) as well, still need to be
    solved before secure messaging can be considered to be an
    operational service.  These problems are independent of the secure
    messaging protocol (i.e., PEM or X.400(1988)) and deal mainly with
    distribution of secret keys to the end users. There is very active
    work going on within the IETF to solve these problems.
  1. MIME and PEM
    There are still problems for messages that are simultaneously a
    multimedia message, as per MIME, and a secure message, as per PEM.
    A PEM encoded MIME message does not allow gatewaying to other
    messaging environments and therefore does not allow any of the
    features inherent within MIME to be exploited along the message
    path. A MIME message that contains PEM encoded body parts can be
    gatewayed but the integrity of the entire message is then not
    guaranteed. This is a real deficiency of both existing approaches
    as it is essential that users are able to simultaneously use
    multimedia and secure messaging. However, once again, the IETF is
    working very hard on solving these problems and solutions can be
    expected, although the solution of the gatewaying of PEM messages
    to other E-mail systems is still unclear.
  1. Dynamic and distributed messaging routing via the Domain Name

System (DNS)

    RFC 822 messaging benefits greatly by having a dynamic and
    distributed mechanism to assist in message routing i.e., Domain
    Name System (DNS). With the support of the DNS, RFC 822 MTAs are
    able to directly route to other RFC 822 MTAs and thus deliver
    messages with a minimum of delay. In practice mail often still
    traverses multiple RFC 822 MTAs for a number of reasons e.g., Mail
    Hubs provided for users who turn their machine off when they go
    home, Firewall Hubs for security reasons, etc. However it is
    commonly accepted that between RFC 822 mail hubs the delivery of
    messages is very fast. Typically resolution of routing decisions
    occurs in less than one minute and very often within seconds. In
    general the DNS service is a very valuable service that functions
    well in practice.
  1. Support for Character sets
    Together with the MIME specification for content types, an
    extension for RFC 822 headers was defined that allows for usage of
    multiple character sets in names, subject etc. in RFC 822 headers
    [9]. This allows (European) users to use their preferred character
    set to support their language not only in the contents of a

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    message but also in the headers.
  1. MIME capable gateways
    It is clear that to provide a seamless service to all users
    regardless of whether they are using RFC 822 or X.400 services, a
    widely available set of well run and standardised RFC 822 to X.400
    gateways must be in place. For InterPersonal Messaging (IPM) based
    on US ASCII there are already a large number of such standardised
    (i.e., X.400-to-RFC 822) gateways deployed. To ensure seamless
    gatewaying between MIME and X.400 multimedia users, these existing
    text based gateways must be either upgraded to or replaced with
    multimedia messaging gateways. A number of proposed Internet
    standards to solve these problems, for both X.400(1984) and
    X.400(1988) and generated within the MIMEMHS work group of the
    IETF, have been completed [4].
  1. Access to fax, teletex, telex or physical delivery
    For the moment, there is no standardised way for RFC 822 users to
    access gateways to the above services except by indirect access to
    X.400(1988) systems (i.e., concatenated gateways of RFC 822 to
    X.400(1988) and then onwards to the appropriate X.400(1988) Access
    Unit). Although even this indirect method would require some
    further work on standardising mappings between RFC 822 addresses
    and X.400(1992)'s X.121 addresses. As well some experiments within
    the RFC 822 world are occurring on routing fax messages.
  1. Operational support
    Generally, RFC 822 messaging services are delivered on a 'best
    effort' basis and thus service level agreements requesting
    stringent response times to operational problems or guaranteed
    delivery times for messages are difficult to agree. This phenomena
    might be a result of the distribution and delegation of authority
    to organisations updating the RFC 822 MTA's routing mechanism
    i.e., DNS. As a result it makes it hard to reach a 'one stop
    shopping' agreement for RFC 822 messaging services.
  1. Notifications
    The RFC 822 service provides a minimum amount of base protocol
    support for messaging users. It could be argued that the RFC 822
    protocol is simplified by this choice and thus software that
    implements the standard need be smaller in size and easier to
    build. However some features e.g., delivery & receipt
    notifications and UA capabilities registration, would be commonly
    accepted as being desirable from a user standpoint and thus

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    desirable extensions to RFC 822. Some operational problems
    relating to reliability could be minimised by technology that has
    a standardised support for positive and negative notifications of
    messages. RFC 822, as compared to X.400, technology does not yet
    support positive notifications (although there is work starting
    within the IETF to extend RFC 822 to support delivery
    notifications). However within RFC 821 transport system (i.e.,
    SMTP) there are standardised negative notifications that work
    well.  Alternatively X.400 technology, deployed over TCP/IP (using
    STD 35, RFC 1006), may help to address the lack of adequate
    service quality - notification support - when using E-mail within
    the Internet.
  1. Portability of RFC 822 products
    There are only a few mailbox formats in general use by RFC 822
    software, one being the 'bin/mail' format and the other 'MH'
    format.  This 'standard' mailbox format is a definite benefit for
    RFC 822 users as it allows them to change RFC 822 UAs (e.g.,
    upgrading to MIME RFC 822 UAs) whilst not compromising or
    converting their existing archived mail, which may comprise 1000s
    of archived messages.
  1. System support for RFC 822 products
    Normally, RFC 822 MTAs and UAs come pre-installed on UNIX
    workstations. As a result, users are spared the effort of
    installing RFC 822 MTA software. If for some reason, a user or
    mail administrator should wish to install a different MTA or UA to
    the pre-installed system, there exists a large number of easily
    available (i.e., via widespread distribution amongst many FTP and
    other information servers) public domain RFC 822 MTAs and UAs.
    Both of the above points encourages the spread and eases the
    installation of software for the RFC 822 messaging service and in
    many ways explains the size and importance of the installed base
    of RFC 822 systems. To illustrate the extent of RFC 822 / MIME
    products, a non-comprehensive list of available MIME enhanced RFC
    822 products follows; ELM 2.4, MH 6.8, Sun Mailtool, HP Mpower
    Desktop, Lotus cc:Mail (unconfirmed), Zcode Zmail, Frontier
    Super-TCP for Windows, PMDF (VAX VMS), Pine, C-Client (library
    routines), Metamail (viewer only), Andrew-MIME gateway.
  1. UA capability registration
    The IETF MHS-DS working group has defined how X.400 and RFC 822
    User Agent capabilities can be stored in X.500 directory services.
    This work is still ongoing.

RARE WG-MSG Task Force 88 [Page 18] RFC 1616 X.400(88) for European Academics and Research May 1994

5.3. X.400 - 1984 and 1988

 X.400(1988) substantially upgrades and enhances the X.400(1984)
 standards. A number of new functions have been incorporated within
 X.400(1988). A description of the most important features of X.400 -
 1984 and 1988 - follows.
  1. Notifications
    X.400(1984) provides four notifications - positive and negative
    delivery notifications and positive and negative receipt
    notifications. These notifications allow users to ensure
    successful message delivery or that the message was read. The
    delivery notifications are also used by service operators in their
    fault escalation procedures.
  1. Binary Data Transfer
    X.400(1984) allows binary data transfer to be transported without
    the necessity of character encoding. The ability to transfer files
    of whatever type is a valuable end user service.  As well the lack
    of any necessary character encoding allows users to utilise the
    received data without needing any character decoding software.
  1. Multiple Body Parts
    The ability to send multiple body parts within one message gives
    the user the ability to send multiple logical components within
    one message. This is a natural mechanism for users as it mirrors
    the real life situation of being able to send within one message,
    a letter, a word processor file, a spreadsheet file, etc.
  1. Feature rich messaging model
    The features of X.400 are very rich. This provides benefits for
    users as vendors are able to provide applications that can utilise
    these extensive features in an interoperable manner due to the
    standardisation of the features within X.400.
  1. Clear messaging model
    X.400(1984), as one of its most wide reaching achievements, has
    popularised within the market a consistent and clear model to
    describe message handling systems. The decomposition of a message
    handling system into UAs, MSs, MTAs, MTS - ADMDs and PRMDs and
    Access Units / Gateways has proved to be an extremely useful tool
    for users and vendors to understand and communicate their
    messaging needs or solutions.

RARE WG-MSG Task Force 88 [Page 19] RFC 1616 X.400(88) for European Academics and Research May 1994

  1. Multiple lower layer networks
    X.400 has embraced the concept that there are different technology
    lower layer networks. This concept even allows multiple logical
    networks of the same technology to be supported. X.400 allows the
    messaging service to fully function even though the underlying
    network is varying. In the real world of a non-uniform network
    layer this is an extremely powerful capability.
 The list of major X.400(1988) extensions to X.400(1984) follows:
  1. Distribution Lists (DLs)
    A powerful mechanism for arbitrarily nested Distribution Lists
    including the ability for DL owners to control access to their
    lists and to control the destination of non delivery reports.  The
    current endemic use of DLs in the R&D community makes this a
    fundamental requirement for any service. X.400(1988) uses X.500 to
    provide a standardised support for DLs, although there have been
    some needed standardised enhancements relating to the CCITT
    defined DLs by the IETF MHS-DS work group. The provision of
    powerful nesting capabilities plus management mechanisms for DL
    owners within X.400(1988) DLs are features providing attractive
    benefits for users and DL managers.  There is already 'running
    code', via the COSINE Explode project which is implementing the
    MHS-DS based enhancements. The project builds upon experience
    gained within a number of networks e.g., JNT and provides:
  1. implementation of MHS-DS enhancements related to the

X.400(1988) DLs

  1. archiving of messages received by a DL.
  2. access by users to the DL archive via e-mail.
  3. subscription to a DL by users via e-mail.
  1. Message Store (MS)
    The Message Store provides a server for remote UAs on workstations
    and PCs enabling messages to be held for their recipient, solving
    the problems of non-continuous availability of such UAs. The
    message store allows mobile workers, small offices and local
    schools to become active messaging users in a cost effective
    manner. The message store provides powerful selection mechanisms
    allowing the user to select messages to be transferred between the
    store and the workstation. This facility is not catered for
    adequately by the P3 protocol of X.400(1984) and provides a major
    incentive for transition.

RARE WG-MSG Task Force 88 [Page 20] RFC 1616 X.400(88) for European Academics and Research May 1994

  1. X.500 Directory names
    Support for use of Directory Names in MHS will allow a transition
    from use of O/R addresses to Directory Names when X.500
    Directories become widespread, thus removing the need for users to
    know about MHS topological addressing components.
    The ability for X.400(1988) messages to contain directory names
    instead of the O/R addresses is a powerful feature for users as it
    frees them of the necessity to insert O/R addresses containing
    routing information but allows them to insert the more natural
    directory names. However, the management of the large amounts of
    distributed data contained within the directory is problematic in
    that it involves a number of organisational issues and not just
    software issues. A number of X.400(1988) UAs which allow users to
    insert directory names instead of O/R addresses have already been
    developed.
  1. Support for EDI
    Through the definition of Pedi, as defined in X.435, X.400(1988)
    offers integrated support for EDI messaging. The CEC TEDIS program
    has mandated X.400 as the main carrier for EDI, and standardised
    how EDI transactions are inserted into X.400 messages (i.e., Pedi
    and P2). This provides a strong incentive to provide native
    X.400(1988) services to users and applications thus encouraging
    commercial EDI traffic to migrate to X.400(1988).
  1. Secure Messaging
    The provision of secure messaging services including
    authentication, confidentiality, integrity and non-repudiation as
    well as secure access between MHS components are important
    benefits for the R&D community. The base standards are adequate
    for security, however organisational and software issues need
    still to be solved. Organisational issues of globally scaling the
    distribution of secret keys is still unsolved. Software issues of
    how end users will be able to comfortably and securely input
    secret keys of length 512 -> 1024 bits into security software need
    to be solved.
  1. Multimedia
    The definition of a number of additional body parts plus the
    ability to define new body parts (e.g., Word Processor formats,
    Excel documents, etc.) provides the basis for multimedia services
    over X.400(1988). As well, the newly defined General Text body
    part supports multinational character sets (except for ISO 10646)

RARE WG-MSG Task Force 88 [Page 21] RFC 1616 X.400(88) for European Academics and Research May 1994

    without the need for transmission encoding. However, unlike MIME,
    X.400(1988) is only specifying a standard for multimedia
    messaging. To achieve multimedia document exchange, there is a
    further text exchange standard such as ODIF, Hytime, etc., needed.
  1. Character set support for extended addressing
    A highly desirable potential benefit for European R&D users is
    provided by the extended character set support(i.e., T.61) within
    addresses. Nearly all European languages, except for Greek and
    Cyrillic, are supported by the T.61 teletex encoding. Further
    extensions to X.400 for support of extended character sets has
    been defined by the RARE WG on character sets and RARE WG on
    messaging [15].
  1. Physical Delivery Services
    This standardised method for a message to be delivered on a
    physical medium, such as paper, through the normal postal service
    is useful when trying to reach a very wide number of (non-
    electronically reachable) recipients. In effect this service
    provides an ability to 'go the last mile' and communicate with
    users previously not easily reachable e.g., farmers, etc.
  1. General Extension Mechanism
    One of the major assets of X.400(1988) is the extension mechanism.
    This is used to carry most of the extensions defined in these
    standards, but its principal benefit will be in reducing the
    trauma of transitions to future versions of the standards.
    Provided that implementations of the X.400(1988) standards do not
    try to place restrictions on the values that may be present, any
    future extension will be relayed by these implementations when the
    extension is not critical, thus providing a painless migration to
    new versions (1992 and beyond) of the standards.
  1. UA Capability Registration
    With the extra functionality available to X.400(1988 and
    especially 1992) UAs (i.e., extra non-IA5 body parts, secure
    messaging, etc.) it is expected that the demand to register UA
    capabilities will increase. In that respect X.400(1988)'s ability
    to query X.500, where such capabilities would be stored, is a
    significant potential benefit for users.

RARE WG-MSG Task Force 88 [Page 22] RFC 1616 X.400(88) for European Academics and Research May 1994

  1. X.500 support for MTA routing
    The piloting of X.500 to support MTA routing within the R&D
    community has already commenced, on a small experimental scale,
    via the Longbud project co-ordinated by the IETF MHS-DS work
    group. Some concrete benefits promised by X.500 based routing are:
  1. routing based upon content types, security, transport stacks

and other criteria allow optimum routing paths to a

      destination MTA to be chosen. (There is presently no such
      similar capability within the DNS).
  1. allowing the routing information to be inserted and modified

in a distributed manner reduces (if not eliminates) the

      necessity of central distribution of static routing tables.
      The consequent reduction in manpower to co-ordinate MTA
      routing plus the increase in scalability of the service
      allows a truly global messaging service to be put in place.

6. Migration to X.400(1988)

 What is clear from the previous chapters is that;
  1. The resources, human or financial, to operate multiple wide

area messaging services connecting together independent

      organisations are high. As such it is desirable to try and
      keep to a minimum the number of such services. This statement
      is true for the R&D community but is also highly likely to be
      valid for the general European industry.
  1. There are two publicly available technological standards

that can be used by open communities, such as the R&D

      community and public service providers: the X.400(1984 and
      1988) recommendations and the Internet RFC 822 / MIME / PEM
      standards.
  1. There is an established very large global user base of

Internet RFC 822 and X.400(1984) messaging services. Both

      services have their own momentum within different parts of
      the user community, both are still developing and growing
      fast.
 From the above discussion, it is clear that the infrastructure
 services that have to be supported within these open communities, and
 especially within the R&D community, are RFC 822 / MIME / PEM,
 X.400(1984) and X.400(1988). X.400(1988) will be the preferred
 protocol for inter-organisational connection for European industry
 and government and parts of the European R&D community. RFC 822 /

RARE WG-MSG Task Force 88 [Page 23] RFC 1616 X.400(88) for European Academics and Research May 1994

 MIME / PEM will be the preferred protocol suite for inter-
 organisational connection for the Internet community and, as products
 are already widely available, it is the preferred protocol for parts
 of the European R&D community.
 The goal of European pervasive messaging - incorporating Industry,
 Government and Academia - would be best accommodated and reached by
 the establishment of a single messaging service.  However taking the
 above into account, this is not feasible, as X.400 and RFC 822 based
 services will be around for a long time to come. To increase the
 functionality of Wide Area E-mail services there is a clear necessity
 to:
  1. migrate RFC 822 services to a RFC 822 / MIME / PEM service.

A MIME based service offers more functionality to the user

      than a plain RFC 822 service.
  1. migrate existing X.400 services to a X.400(1988) service.

Due to the lack of scalability of the X.400(1984) service in

      terms of extra functionality, it will become increasingly
      difficult to meet the needs of research users of existing
      X.400(1984) services unless an X.400(1988) service is put
      into place.
  1. provide a transparent gateway between X.400(1988) and RFC

822/MIME/PEM. For the European R&D community it is essential

      to have a transparent gateway between the X.400(1988) service
      and the RFC 822 / MIME / PEM service, thus ensuring
      connectivity between these two services with a maximum
      functionality.
 Such a gateway is technically feasible and it is an essential part of
 an unified E-mail service. Without such a standardised gateway the
 overall E-mail service would deteriorate.
 The lack of open standards for the PC LAN messaging systems
 discourages their use as 'backbone' messaging technologies within
 open communities. However the products that these systems deliver to
 end users ensures that their already large share of the messaging
 market will continue to exist for some time. Thus it is also
 essential that strategies that allow these systems to be 'seamlessly'
 integrated within the global messaging community are put in place.
 Not least due to the indications that the main messaging vendors are
 developing X.400(1988) and RFC 822/MIME gateways, a strategy to link
 these systems together via X.400(1988) and RFC 822/MIME should be
 developed.

RARE WG-MSG Task Force 88 [Page 24] RFC 1616 X.400(88) for European Academics and Research May 1994

 To make migration to a X.400(1988) service feasible, extensive
 migration and coexistence options for various non-X.400(1988) users
 have to be developed. Main issue in each migration strategy remains
 the co-operation of the users. The migration needs to be user-driven,
 i.e., the users need to be convinced of the added functionality
 (versus the cost) of migrating towards X.400(1988). A detailed
 summary of the different issues and possible problems involved in the
 transition to a X.400(1988) based messaging service, with respect to
 what are commonly accepted as the four most important messaging
 services: RFC 822, MIME and PEM; X.400(1984); MAIL-11 and PC LAN
 messaging systems are presented in this chapter.

6.1. PC LAN E-mail systems

 To provide coexistence and migration the usage of gateways is
 unavoidable. The quality of these gateways, with regard to:
  1. Transparency (gatewaying multimedia messages, transparent

addressing)

  1. Manageability
  2. Reliability
 has to be improved. Ultimately through usage of APIs like MAPI and
 CMC, the users interface hopefully will become independent of the
 mail protocol that is used. It will then be expected to be possible
 to let the user retain his preferred mail user interface, while the
 protocol used migrates to X.400(1988).
 Via the use of these APIs it may be possible to access the full
 features of X.400(1988) while retaining a proprietary PC LAN UAs.
 This way a PC LAN can be easily connected to a X.400(1988) backbone.
 This usage of APIs to ease migration for end users should be
 encouraged.
 The migration of PC LAN E-mail systems will likely be driven by the
 commercial vendors of mail enabled applications, such as UAs, Work
 Group Systems, Task Flow Systems plus X.400(1988) MTAs and gateways
 able to serve these applications via these new APIs.

6.2. RFC 822, MIME and PEM services

 A migration from RFC 822 / MIME and PEM services to X.400(1988) needs
 to be formulated for those management domains that wish to effect
 this change. As well a long term transition and coexistence phase
 needs to be accommodated due to the existing base of RFC 822 users.
 An understanding of the issues involved in migrating from RFC 822 to
 X.400(1988) messaging services is essential before any rational
 decisions on migration can occur.  Certainly one, if not the main,

RARE WG-MSG Task Force 88 [Page 25] RFC 1616 X.400(88) for European Academics and Research May 1994

 issue in such a migration is that the migration must allow a
 transition period where maximum functionality between both services
 exists. Any migration must be aware that RFC 822 messaging services
 are a 'moving target'.
  1. Ease of transition as perceived by an RFC 822 user mandates

that the user's existing mail folders are converted into the

    new mail product's folder system flawlessly.
  1. The RFC 822's user's e-mail address should remain the same

even after a migration. (i.e., the user keeps the same address

    that has two different notation forms: X.400 and RFC 822).
  1. Users contemplating a migration will be stimulated to do so

if they experience no loss of service as regards MIME and

    X.400(1988) gatewaying; are still able to insert RFC 822
    style addresses into the X.400(1988) UA and are provided with
    high performance X.400-to-RFC 822 gateways.
  1. The added connectivity provided by X.400(1984 or 1988)

gateways to fax, telex, post etc. plus additional X.400 users

    that the user is able to reach easily (whilst not losing
    connectivity to RFC 822 addresses) plus the additional
    functionality of X.400(1988) possible when communicating with
    X.400(1988) users will also act as a stimulant to a
    migration.
  1. The functionality provided by RFC 822 / MIME products will

be the yardstick that an RFC 822 user compares an offered

    X.400(1988) product with. As such X.400(1988) products must
    provide some basic and important functions like: Character
    Set support via GeneralText; Multimedia capability via
    Extended Body Parts; low message delays within the seconds
    time scales and ease of configuration of products. At present
    there is no RFC 822 equivalent to X.400 delivery and receipt
    notifications and as such these functions are seen as extra
    functionality by the user.
  1. A follow on to the extra functionality point above is that

present RFC 822 users, most likely commercial users, that

    want to be able to use EDI or other mail enabled applications
    that need security, message audits and positive confirmations
    will be encouraged to migrate to X.400(1988). A decision to
    use X.400(1988) in this case would be especially attractive
    for those commercial RFC 822 users that are already operating
    multiple lower layer networks. As X.400(1988) accommodates
    multiple different network layers easily, the cost to migrate
    could be considered quite small.

RARE WG-MSG Task Force 88 [Page 26] RFC 1616 X.400(88) for European Academics and Research May 1994

6.3. X.400(1984) services

 A number of problems can be identified in a migration from
 X.400(1984) to X.400(1988). They are summarised as,
  1. OSI supporting layers are mandatory in the ISO10021 MOTIS

standard, while the support of the complete OSI stack (normal

    mode ) is optional in the otherwise equivalent CCITT
    X.400(1988) specifications. It is thus recommended that the
    migration from X.400(1984) should be straight to ISO 10021
    i.e., straight to use of the full OSI stack with normal mode
    RTS.
  1. There is a negative impact on quality of service caused by

implementation decisions related to the 'General Extension

    Mechanism'. To overcome this negative impact no minimal
    X.400(1988) MTAs, which relay the syntax but understand none
    of the semantics of extensions, should be used.
  1. All X.400(1988) MTAs should generate reports containing the

extensions that are present in the original message and route

    such reports through the DL expansion hierarchy where
    appropriate.
  1. Choice of standards to be used within mixed X.400(1984 and

1988) management domains needs to accommodate in one option

    the danger of undetectable routing loops from incorrectly
    configured routing entries and in another option the problem
    that systems that have fixed the routing loop problem may not
    all be consistently implemented due to ambiguities within the
    standards. The choice of which of these two options a
    management domain uses internally has no impact on external
    management domains.
  1. DDA support is needed by X.400(1984) systems to address

X.400(1988) Common Name Attribute users [2].

  1. Minimum loss of service quality mandates that downgrading of

X.400(1988) body parts to X.400(1984) bodyparts be done

    according to the MIMEMHS specifications [4].
  1. To enhance connectivity to both X.400(1984 and 1988)

management domains without degradation of X.400(1988)

    service, management domain entry points that support both
    X.400(1984 and 1988) are recommended.

RARE WG-MSG Task Force 88 [Page 27] RFC 1616 X.400(88) for European Academics and Research May 1994

  1. Ensuring that no X.400(1988) MTAs transit via X.400(1984)

MTAs. This allows no degradation of X.400(1988) service

    quality [17].
 The consequence of the last point is that the existing European
 Research X.400(1984) - formerly COSINE MHS - MTA RELAY backbone
 should be one of the first MTA communities to migrate to X.400(1988).

6.4. Mail-11 services

 The Mail-11 (also known as DECnet mail) e-mail service is the major
 e-mail service used within the High Energy Physics and Space Physics
 Analysis Networks (i.e., HEPnet and SPAN) and is the native e-mail
 service present on VMS operating systems. The Mail-11 service is
 considered the most popular service by the large HEPnet / SPAN
 community. Mail-11 provides also large and easy to use gateways to
 other E-mail protocols, like X.400 (84), RFC 822 (SMTP over TCP/IP,
 DECnet and X.25, BSMTP over NJE), and PC LAN E-mail services.
 Jointly with the "old style" Mail-11 UA, the DECnet Phase V (OSI
 CLNS) service provides the native capability to run X.400 (88) and
 X.400(1984) services. There is thus the potential for X.400 (88)
 services to become available as soon as the HEPnet / SPAN community
 migrates to DECnet Phase V. However the availability of VMS based UAs
 for the X.400(1988) service is still very limited and is thus forcing
 users to continue to stay with their Mail-11 UA (and thus the Mail-11
 service).
 Users in HEPnet / SPAN are demanding enhancements to their mail
 services to support multimedia and delivery / read receipt services.
 This is a strong driving factor for good X.400(1988) UAs to become
 available soon to allow users to properly use the available
 X.400(1988) service of DECnet Phase V.

7. Benefits of migrating to X.400(1988) and the involved costs

 The actual as compared to the potential benefits of migrating from
 one's existing mail system to a new mail protocol is very dependent
 on good products, good organisation of the migration and a degree of
 commitment that the transition is worth the cost. Quantifiable and
 accurate cost / benefit ratios for such a migration are not possible
 within the decentralised European R&D environment and as such are not
 generated.
 We have in this chapter listed the benefits that such a migration to
 X.400(1988) achieves. We have also given an indication of the
 relative costs of such a migration. Provided that there are good
 products, and taken in conjunction with the recommendations of

RARE WG-MSG Task Force 88 [Page 28] RFC 1616 X.400(88) for European Academics and Research May 1994

 Chapter 8 and Appendices A and B, the task force is confident that
 these potential benefits will translate into actual benefits and be
 worth the costs incurred.

*Benefits*

 Below is a list of non-technically oriented benefits and the features
 of X.400(1988) that enable these benefits to occur. The benefit of,
  1. efficient and innovative communication within Europe is

assisted by establishing an X.400(1988) messaging service

    that integrates European industry, government and academia;
  1. an increase in business efficiency by the use of EDI (for

example automatic processing of business forms, exchange of

    business contracts, etc.) is enhanced by the security aspects
    of X.400(1988) i.e., non-repudiation, authentication,
    confidentiality, integrity plus secure access between MHS
    components.
  1. allowing European users to communicate in their native

European languages is brought about by the GeneralText body

    part of X.400(1988).
  1. remote users and Small and Medium size Enterprises(SME)

using e-mail for electronic commerce is encouraged by

    reducing the entry level costs for use of e-mail. An SME's
    use of Remote UAs in conjunction with a service provider's MS
    -instead of purchasing their own MTA - is accommodated by
    X.400(1988).
  1. providing global messaging for all e-mail users, but

recognising the existing market realities of heterogeneous e-

    mail systems, would be enhanced by the establishment of
    gateways to X.400(1988).
  1. being able to recover costs by charging and accounting for

messaging services back to users - this is especially

    important for commercial service providers - is brought about
    by the message auditing capabilities of X.400(1988).
  1. communication with users that have no access to E-mail (for

example if such users are defined within Distribution Lists)

    is enhanced by X.400(1988)'s support for gateways to physical
    delivery, fax, telex, teletex, etc.

RARE WG-MSG Task Force 88 [Page 29] RFC 1616 X.400(88) for European Academics and Research May 1994

  1. building upon the existing X.400(1984) infrastructure (i.e.,

reduction of establishment costs) is brought about by

    migrating the X.400(1984) infrastructure to X.400(1988).
  1. a reduction in manpower (and thus costs) to manage a global

messaging service is brought about by the messaging service's

    ability to utilise the global distributed directory for
    management information.
  1. the messaging infrastructure to meet new user requirements

is enhanced by the support for General Extensible Mechanism.

  1. making E-mail more user friendly is brought about by a

messaging service that allows the use of the more natural

    directory names in E-mail addresses.
  1. increased effectiveness of messaging by the use of DLs is

brought about by X.400(1988)'s support of powerful nesting

    capabilities and management for DLs.
  1. an increase in global message delivery performance and

reliability is enhanced by the ability of X.400(1988) to use

    X.500 for MTA routing.
  1. more messages being successfully delivered to mobile or

transient users is enhanced by the provision of the Message

    Store.
  1. multimedia use is enhanced by the ability to define new body

parts and to support multiple types of binary data such as

    audio and video.
  1. establishing optimum and seamless conversion of messages

based upon the capabilities of a user is brought about by the

    ability of X.400(1988) to act upon UA capabilities.

*Costs*

 The generic costs to establish an X.400(1988) pilot service can be
 broken down into:
  1. a cost per backbone of RELAY MTAs (as used by the European

research community - the former Cosine MHS service),

  1. a cost per service provider,
  2. a cost per organisation,
  3. a cost per user and
  4. a cost per user MTA for migrating to X.400(1988).

RARE WG-MSG Task Force 88 [Page 30] RFC 1616 X.400(88) for European Academics and Research May 1994

 To bring about the benefits, mentioned above, certain costs will be
 incurred and they are summarised below:
  1. Cost per backbone of RELAY MTAs (as used by the European

research community - the former Cosine MHS service)

  1. The equipment costs of migrating backbone RELAY MTAs.
  1. The establishment of some sort of organisational /

project group to oversee a backbone RELAY MTA pilot.

    As most of the RELAY MTAs are already X.400(1988) capable, there
    is already a MHS Co-ordination service in place that could be used
    for this function and the number of backbone RELAY MTAs is less
    than 100 in number the cost for migrating the RELAY MTA backbone
    is considered relatively low.
  1. Cost per service provider
  1. If the RELAY MTA backbone (formerly Cosine MHS) is

migrated towards X.400(1988), then the remaining cost

         for a service provider for migrating the infrastructure
         towards X.400(1988) is relatively low.
  1. The operational costs for organisational issues, for

example dealing with OID registrations, is low if

         national R&D service providers act as a clearinghouse
         for their own national R&D institutions e.g.,
         Universities.
  1. Cost per organisation, end user and MTA
  1. The operational costs of migrating end users and their

MTAs in management domains to X.400(1988) are higher

         than the costs involved with migrating the
         infrastructure. This is due to the order of at least 10
         to 100 times more MTAs, as compared to the service
         providers, that would be involved with a migration to
         X.400(1988). As the infrastructure needs to migrate
         first, the costs for the end user MTAs can be reduced
         by profiting from the migration experience of the
         service providers.
  1. The education and training costs for users and system

managers are significant, due to the amount of end

         users and end user MTAs. Any marginal cost savings per
         user which can be made, e.g., by deployment of automated
         tools, should be considered due to the large overall

RARE WG-MSG Task Force 88 [Page 31] RFC 1616 X.400(88) for European Academics and Research May 1994

         savings that accrue.
  1. The costs of any potential disruption of the end user's

messaging service are high - due to the huge numbers of

         end users involved - and as such only a very well
         managed, phased and planned migration should be
         considered.
  1. Software costs
  1. The costs for software development are outside the

scope of this report. However it is clear that cost

         needs to be incurred in order to provide software that
         is easy to install and use. As a result of the work of
         the task force a list of possibly needed components and
         likely changes to existing components can be proposed,
              Modifications, but not new developments, to
                software for:
  1. X.400(1988) MTAs, X.400(1988) UAs, DSAs,

DUAs and MSs.

              New software developments for:
  1. MIME to MHS Gateways, X.400(1988) network

management, mailbox conversion, PC LAN

                     directory synchronisation, PC LAN gateways
                     and UA capability registration.
  1. The distribution costs for any new software (for the

European R&D community) are low if usual academic

         distribution methods - FTP servers, E-mail Based
         servers, Gopher, World Wide Web and Archie - are used.

*Summary*

 Migration towards a X.400(1988) service needs to evolve from the
 inside (the messaging backbone) outward (to the end user MTAs and end
 users themselves). Due to the numbers involved both the costs and the
 benefits associated with the migration increase as the migration
 evolves towards the end users.
 The benefits of migrating to a X.400(1988) service are a feature rich
 well defined open standard with high functionality , scalability, use
 of directory, multimedia and secure messaging capability. The costs
 for migrating a RELAY MTA backbone can be considered relatively low
 whilst the migration of end user MTAs and the migration of the end

RARE WG-MSG Task Force 88 [Page 32] RFC 1616 X.400(88) for European Academics and Research May 1994

 users themselves are relatively high. These costs should of course be
 balanced against the cost of a disrupted service that one might get
 if no migration occurs at all and the current service (e.g.,
 X.400(1984)) reaches the limits of its scalability and/or
 functionality.
 It is important to realise that if end users themselves do not
 experience direct feedback of the benefits from X.400(1988), this may
 make the organisational motivation needed to effect such a migration
 difficult to achieve. In effect, the establishment of a pilot
 X.400(1988) service is and should be driven by the requirements of
 end users and thus achieving end user benefits - as listed above -
 must be given a higher priority within a X.400(1988) service than
 solely the extra service provider benefits.

8. Main Recommendations

 The RARE WG-MSG Task Force on 'The Establishment of an X.400(1988)
 Pan European Pilot Messaging Service' has identified a number of high
 level recommendations for establishing such a
  service. The main high level recommendations are listed within this
 chapter. A more detailed elaboration of these main recommendations is
 given in Appendix A. Appendix A is provided for policy makers wishing
 more background on the main recommendations. As well, a list of very
 detailed guidelines, plus some issues requiring further
 investigation, is given in Appendix B. Appendix B will be especially
 useful for personnel seeking detailed technical guidelines which are
 consistent with the main high level recommendations.

*Recommendations*

  1. Establish a X.400(1988) pilot service encompassing European

Commercial, Government and Academic bodies. Such a pilot

    service to be co-ordinated by using an industry forum where
    all parties could meet. The use of an existing forum, where
    user organisations are well represented, is desirable if
    commercial end users organisation's requirements are to be
    met. The forum should also be open to non-European
    participants.
  1. X.400(1988) end user services should be provided as well as

a X.400(1988) backbone RELAY MTA service within a X.400(1988)

    pilot service. The end user services should be given a high
    priority.
  1. Help an already emerging market place in X.400(1988)

products to prosper by ensuring that a suitable supply of

    high quality X.400(1988) public domain software is available.

RARE WG-MSG Task Force 88 [Page 33] RFC 1616 X.400(88) for European Academics and Research May 1994

    The Internet has proven, that public domain software, free of
    any commercial restrictions, is further rapidly developed, by
    Small and Medium Size Enterprises (SMEs), into derivative
    products suitable for the commercial market.
  1. Any pilot service should be well co-ordinated and result

driven but utilise a distributed market oriented approach. It

    is considered very difficult to organise and plan such a
    pilot under the assumption of a single centrally funded body
    i.e., driven from the 'top'. A more 'market driven' or
    distributed organisation is considered feasible, and likely
    to succeed, if all the market 'players' are fully involved
    i.e., a 'bottom' up approach.
  1. For the academic community - and ever more for the

commercial community - there is a business need to ensure near

    total and 'perfect' integration with the existing and also
    evolving RFC 822 based services.
  1. For the academic community a rapid migration of the existing

X.400(1984) backbone RELAY MTAs, used within the European R&D

    X.400(1984) service, - formerly the COSINE MHS service - is
    considered urgent. This migration will provide a 'bootstrap'
    path for academic organisations to internationally pilot
    X.400(1988) services. Such end user piloting is not
    considered feasible if X.400(1984) backbone RELAY MTAs are
    used for an X.400(1988) service (see Reference [17] for
    technical details).
 The report does not include any recommendations on development and
 deployment of RFC 822 / MIME / PEM related (pilot) services, as these
 are outside of the scope of the Task Force. However, since both
 X.400(1988) and RFC 822 / MIME / PEM will be developed and used
 within the European R&D community, such a pilot should also be
 considered.

9. Security Considerations

 Security issues are not discussed in this memo.

RARE WG-MSG Task Force 88 [Page 34] RFC 1616 X.400(88) for European Academics and Research May 1994

10. Reading List and Bibliography

 This section contains a list of relevant reference documents that can
 be used for further reading.
    [1]         Kille;, S., "Mapping between X.400(1988) / ISO 10021
                and RFC 822", RFC 1327/RTR 2, University College
                London, May 1992.
    [2]         Kille, S., "X.400 1988 to 1984 downgrading",
                RFC 1328/RTR 3, University College London, May 1992.
    [3]         Adie, C.,  "A Survey on Multimedia Projects, Products
                and Standards", RTR 5, Edinburgh University Computing
                Centre, January 1993.
    [4]         Alvestrand, H., and S. Thompson, "Equivalences between
                1988 X.400 and RFC 822 Message Bodies", RFC 1494,
                SINTEF DELAB, Soft*Switch Inc., August 1993.
    [5]         Alvestrand, H.,  Kille, S., Miles, R., Rose, M.,
                and S. Thompson, "Mapping between X.400 and RFC 822
                Message Bodies", RFC 1495, SINTEF DELAB, ISODE
                Consortium, Soft*Switch, Inc., Dover Beach
                Consulting, Inc., Soft*Switch, Inc., August 1993.
    [6]         Alvestrand, H., Romaguera,  J., and K. Jordan,
                "Rules for downgrading messages from X.400/88 to
                X.400/84 when MIME content-types are present in the
                messages", RFC 1496, SINTEF DELAB, NetConsult AG,
                Control Data Systems, Inc., August 1993.
    [7]         IETF MHS-DS Working Group, Works in Progress.
    [8]         Borenstein, N., and N. Freed, "MIME (Multipurpose
                Internet Mail Extensions) Part One: Mechanisms for
                Specifying and Describing the Format of Internet
                Message Bodies", RFC 1521, Bellcore, Innosoft,
                September 1993.
    [9]         Moore, K., "MIME (Multipurpose Internet Mail
                Extensions) Part Two: Message Header Extensions for
                Non-ASCII Text", RFC 1522, University of Tennessee,
                September 1993.

RARE WG-MSG Task Force 88 [Page 35] RFC 1616 X.400(88) for European Academics and Research May 1994

    [10]        Kaliski, B., "Privacy Enhancement for Internet
                Electronic Mail: Part IV: Key Certification and
                Related Services", RFC 1424, RSA Laboratories,
                February 1993.
    [11]        Balenson, D., "Privacy Enhancement for Internet
                Electronic Mail: Part III: Algorithms, Modes, and
                Identifiers", RFC 1423, TIS, February 1993.
    [12]        Kent, S., "Privacy Enhancement for Internet
                Electronic Mail: Part II: Certificate Based Key
                Management", RFC 1422, BBN, February 1993.
    [13]        Linn, J., "Privacy Enhancement for Internet
                Electronic Mail: Part I: Message Encryption and
                Authentication Procedures", RFC 1421, IAB IRTF PSRG,
                IETF PEM WG, February 1993.
    [14]        Jurg, P., and E. Huizer, "The SURFnet electronic mail
                project", SURFnet, EH/PJ932307, July 1993.
    [15]        Alvestrand, H., "X.400 Use of Extended Character
                Sets", RFC 1502/RTR 7, SINTEF DELAB, August 1993.
    [16]        Manros, C.-U., "The X.400 Blue Book Companion", ISBN
                1 871802 00 8, Technology Appraisals Ltd, 1989.
    [17]        Houttuin, J., and J. Craigie, "Migrating from
                X.400(1984) to X.400(1988)", RFC 1615/RTR 9,
                RARE, JNT, May 1994.
    [18]        Nagelhus, I. et al., "Survey of E-mail systems with
                X.400 capability".
    [19]        "A White Paper on X.400(1988)", EMA Report.
    [20]        IAB, IESG, "The Internet Standards Process --
                Revision 2", RFC 1602, March 1994.

RARE WG-MSG Task Force 88 [Page 36] RFC 1616 X.400(88) for European Academics and Research May 1994

11. Terminology

    ADMD     Administration Management Domain
    ASCII    American Standard Code for Information Exchange
    ASN.1    Abstract Syntax Notation One
    AU       Access Unit
    CCITT    Comite Consultatif International de Telegraphique et
             Telephonique
    CEN      Comite Europeen de Normalisation
    CENELEC  Comite Europeen de Normalisation Electrotechnique
    CEPT     Conference Europeene des Postes et Telecommunications
    CONS     Connection Oriented Network Service
    COSINE   Co-operation for OSI networking in Europe
    DL       Distribution List
    DIS      Draft International Standard
    EMA      Electronic Messaging Association
    EN       European Norm
    ENV      Draft EN, European functional standard
    IEC      International Electrotechnical Commission
    IETF     Internet Engineering Task Force [20]
    IPM      Inter-Personal Message
    IPMS     Inter-Personal Messaging Service
    IPN      Inter-Personal Notification
    ISO      International Organisation for Standardisation
    JNT      Joint Network Team (UK)
    JTC      Joint Technical Committee (ISO/IEC)
    MD       Management Domain (either an ADMD or a PRMD)
    MHS      Message Handling System
    MHS-DS   Message Handling Systems use of Directory Service
             Working Group from the IETF
    MIME     Multi-purpose Internet Mail Extensions (extensions to
             RFC 822) [6]
    MOTIS    Message-Oriented Text Interchange Systems
    MTA      Message Transfer Agent
    MTL      Message Transfer Layer
    MTS      Message Transfer System
    NBS      National Bureau of Standardization
    OSI      Open Systems Interconnection
    PEM      Privacy Enhanced Mail [10]
    PRMD     Private Management Domain
    RARE     Reseaux Associes pour la Recherche Europeenne
    RFC      Request For Comments (series of Internet publications)
    RFC 822  RFC describing Internet Message format for Electronic
             mail
    RTR      RARE Technical Report (series of RARE publications)
    RTS      Reliable Transfer Service
    WG-MSG   RARE Working Group on Mail and Messaging

RARE WG-MSG Task Force 88 [Page 37] RFC 1616 X.400(88) for European Academics and Research May 1994

Appendix A - Elaboration on the main recommendations

 The main recommendations of the report are elaborated upon in more
 detail within this appendix.
  1. In order to provide a globally pervasive messaging service,

it is recommended to establish a well operated Pan-European

    X.400(1988) pilot backbone comprising MTAs and MSs,
    connecting partners within Industry, Commercial Service
    Providers, Academia and Public Bodies (CEC, National
    Governments, etc.). The pilot should be open to global
    participation.
  1. In order to maintain the widest connectivity with the

highest possible functionality, gateways should be installed

    that gateway between X.400(1988) and RFC 822/MIME. These
    gateways should follow the specifications of RFC 1327 [1] and
    RFC 1494 et al. [4]. Experience with these gateways should be
    fed back into the appropriate RARE and IETF Working Groups to
    improve the standards.
  1. In order that the 'business needs' of non-R&D organisations

can be inserted at an early stage into the goals of the pilot

    and ensuring that the success of the pilot in meeting these
    goals can be measured and disseminated i.e., to encourage the
    active participation of non-R&D organisations within the
    pilot, it is recommended that an open forum comprising
    industry, service providers, public bodies and academia
    should be used. Preferably an existing forum where end users
    are heavily involved is desirable.
  1. In order for meaningful co-operation between bodies affected

by the pilot to occur and thus hopefully reducing unnecessary

    duplications, it is recommended that there are close liaisons
    and contacts between at least the IETF, RARE, EARN, EUnet,
    RIPE, Y-NET, EEMA, EMA, EWOS, OIW, CEN/CENELEC, ISO, CCITT,
    CEC and European governmental bodies and those involved
    within the pilot. The suggested mechanism for a meaningful
    liaison is that enough participants of the above
    organisations attend the common forum mentioned above. It is
    also suggested that as much as possible e-mail distribution
    lists be used to communicate between forum participants.
  1. In order that the pilot have measurable results, it is

recommended that the pilot shall be implemented in phases. It

    is considered that at least two phases are needed:

RARE WG-MSG Task Force 88 [Page 38] RFC 1616 X.400(88) for European Academics and Research May 1994

  1. phase 1 - initial short start up phase with a small

number of participants. The result of this phase is

         that any needed procedures, co-ordination mechanisms,
         etc. are put into place for the large scale piloting of
         phase 2.
  1. phase 2 - phase with a wide Pan-European participation.

The result of this phase should be a proof of scaling

         of the pilot X.400(1988) service i.e., the goals of the
         pilot as defined in Chapter 1 are met. It is expected
         that upon successful completion of this phase a natural
         evolution to a global deployment of a X.400(1988)
         service will have started.
  1. In order to rapidly complete phase 1 of the pilot and that

the pilot is at least Pan-European in scope, it is

    recommended that; a number of R&D service providers, one each
    from several European countries; at least 2 North American
    R&D service providers; at least 1 Japanese R&D service
    provider and a small number of commercial service providers
    and commercial organisations are actively involved in phase
    1.
  1. In order to stimulate the creation of an economically viable

market place for X.400(1988) products (i.e., MTAs, UAs, etc.)

    (i.e., users are willing to purchase such products), it is
    recommended that a suitable minimum number of new software
    implementations and or modifications to existing software
    implementations be funded. The resulting software to be
    inserted into the Public Domain free of any financial
    restrictions on further commercial exploitation. By using
    this mechanism, Small and Medium Size Enterprises (SMEs) will
    be encouraged to commercially exploit such products.
  1. Due to the strong influence of the R&D community within the

pilot plus the desire to produce standardised products

    quickly and pragmatically, it is recommended that any
    standards proposed within the scope of an X.400(1988) pilot
    (for example standards re: character sets and body parts
    gatewayed to and from X.400(1988) and RFC 822 / MIME) are
    conformant to and candidates for Internet standardisation. As
    a concrete example of the standardisation process, this means
    that at least two independent software implementations, for
    each product category, (of which one product preferably in
    the Public Domain) must be proven as interworking to a
    proposed standard before the proposed standard can be
    elevated to draft standard [20].

RARE WG-MSG Task Force 88 [Page 39] RFC 1616 X.400(88) for European Academics and Research May 1994

  1. To ensure that there is a market driven demand for

X.400(1988) products within the commercial market place, it

    is recommended that the maximum number of Public Domain
    implementations that are funded, by any one public funding
    organisation, is two. It is desirable that at least one other
    product, preferably commercially based and not within the
    Public Domain, is produced.
  1. In order that any necessary information required for the

effective operation of the X.400(1988) pilot, including not

    least OID assignments, mapping rules, information about
    interconnection partners, naming authority information be
    made widely available, it is recommended that an
    electronically accessible information base be established.
  1. In order that any necessary organisational issues needed for

a deployment of an X.400(1988) service have a body in place

    to deal with this issue, it is recommended that the pilot
    either identify and list which bodies are responsible for
    which issues or else actively ensure that a suitable body is
    being put in place.

Appendix B - A number of detailed guidelines.

 The Task Force has the following detailed guidelines:

*Product and operational service guidelines*

  1. To ensure that there is no degradation of X.400(1988)

service between X.400(1988) originators and destinations, the

    topology of the MTS must be such that no X.400(1984) MTA acts
    as a relay between any two X.400(1988) users.
  1. As the existing R&D X.400(1984) service (formerly COSINE

MHS) now comprises a large number of X.400(1988) capable

    RELAYs, it would be relatively straight forward that the
    existing COSINE MHS RELAYs be one of the first communities
    that are migrated to X.400(1988) capabilities. This would
    ensure that X.400(1988) MTAs using the RELAY backbone
    experience no loss of service.
  1. To be able to operate an X.400(1988) service a properly

operated X.400(1988) infrastructure should be established,

    consisting of X.400(1988) MTAs, X.400(1988) MTAs with
    downgrading capabilities according to RTR 3, Message Store
    services and gateways to RFC 822 based upon RTR 2 and
    extended gatewaying functionality for multimedia mail.

RARE WG-MSG Task Force 88 [Page 40] RFC 1616 X.400(88) for European Academics and Research May 1994

  1. To ensure maximum use of the OSI supporting layers plus

support of normal mode RTS, it is recommended that a

    migration to ISO 10021 is effected i.e., straight to use of
    the full OSI stack with normal mode RTS.
  1. To ensure maximum quality of service as impacted by

implementation decisions related to the 'General Extension

    Mechanism', it is recommended that no minimal X.400(1988)
    MTAs, which relay the syntax but understand none of the
    semantics of extensions, should be used.
  1. It is recommended that all X.400(1988) MTAs should generate

reports containing extensions copied from the subject message

    and route reports through the DL expansion hierarchy where
    appropriate.
  1. It is recommended that all X.400(1984) UAs are able to

generate and display DDAs. This will allow such systems to

    address X.400(1988) Common Name Attribute users.
  1. To enhance connectivity to both X.400(1984 and 1988)

management domains without degradation of X.400(1988)

    service, management domain entry points that support both
    X.400(1984 and 1988) are recommended.
  1. To ensure total connectivity between RFC 822 domains

migrating to X.400(1988), it is recommended that a local

    X.400-to-RFC-822 gateway is made operational or a reliable
    service agreement for the external provision of such a
    gateway is effected before any migration begins.

*Migration utilities needed*

  1. It is considered very helpful if conversion utilities that

allow a flawless conversion of an RFC 822 user's existing

    mail folders to a X.400(1988) product's folder system be
    implemented. However further investigation is needed before
    recommending that such tools be made a mandatory part of any
    funded software development.
  1. It is recommended that the ease of configuration of

X.400(1988) products is made as automatic as possible.

    Consideration should be given to a) modern user interfaces b)
    automatic processing of 'old RFC 822' configuration files
    into the 'new X.400(1988)' configuration files i.e., a reuse
    of the user's previous options and configurations should be
    the result. If a 'simple' configuration interface is needed
    it should be as compatible as possible with the present RFC

RARE WG-MSG Task Force 88 [Page 41] RFC 1616 X.400(88) for European Academics and Research May 1994

    822 mailer's i.e., this concretely means editing of ASCII
    files.

*Issues for further study*

 The pilot X.400(1988) messaging service must ensure that the issues
 listed below are either being investigated by an appropriate body or
 if not initiate actions to properly address them. The issues have
 been grouped under Products, Organisational and Deployment.
  1. Products
  1. Any X.500 DSAs, DUAs, APIs e.g., LDAP, etc. changes

needed to support X.400(1988) messaging.

  1. X.400(1988) MTAs, UAs, MSs, gateways to RFC 822/MIME

and X.400(1984) plus gateways to other messaging

         systems e.g., Microsoft Mail, Lotus cc:Mail, etc.
  1. User Interfaces that integrate X.400(1988) UAs and

X.500 DUAs with user applications such as Word

         Processors, etc.
  1. E-mail network management software both for users and

administrators

  1. Organisational
  1. trusted network for security (i.e., the distribution of

security keys) and whether this trusted network should

         or can be the same as the PEM trusted network presently
         under deployment.
  1. usage of PEM within X.400(1988).
  1. PEM to and from X.400(1988) gatewaying.
  1. how to register and publicise object IDs for

X.400(1988).

  1. addresses are well publicised of PRMD and ADMD

registration authorities.

  1. creation and modification authority for X.400-to-RFC-

822 mapping rules is defined.

  1. creation and modification authority for MTA routing

rules is defined.

RARE WG-MSG Task Force 88 [Page 42] RFC 1616 X.400(88) for European Academics and Research May 1994

  1. what methods should be used to liaison to other bodies

like IETF, ISO, EEMA, EMA, etc.

  1. ensuring that any Public Domain software needed for the

X.400(1988) service is distributed widely, quickly and

         efficiently.
  1. Deployment
  1. which services should start such a migration (i.e.,

COSINE MHS RELAYs, Universities, other).

  1. the topology of the X.400(1988) MTS.
  1. addressing of users between X.400(1984 and 1988) and

RFC 822 e.g., how will X.400(1988) T.61 address

         components be processed by X.400(1984) and RFC 822
         systems.
  1. which X.400(1988) body parts MUST be supported by the

research community.

  1. if any new APIs - or modified APIs - are needed for

X.400(1988) and messaging in general.

  1. the specifications and development of any needed Public

Domain software.

  1. what existing Public Domain software should be modified

to accommodate X.400(1988) systems.

  1. how rapidly to deploy the X.400(1988) service.
  1. ensuring that there is 'little or no loss of service'

in any migration from X.400(1984), or RFC 822, to

         X.400(1988).
  1. considering what Value Added Services, based upon

X.400(1988), could be started to encourage uptake of

         X.400(1988).

RARE WG-MSG Task Force 88 [Page 43] RFC 1616 X.400(88) for European Academics and Research May 1994

Authors' Addresses

 Only the two editors' complete addresses are listed here:
 Erik Huizer (Task Force chair)
 SURFnet bv
 P.O. Box 19035
 NL-3501 DA  Utrecht
 Europe
 Phone: +31 30 310 290
 RFC 822: huizer@surfnet.nl
 X.400:   S=huizer;O=SURFnet;PRMD=surf;ADMD=400net;C=nl;
 James A. (Jim) Romaguera
 NetConsult AG
 Berner Technopark
 Morgenstrasse 129
 CH-3018 Bern
 Europe
 Phone: +41 31 998 4141
 RFC 822: romaguera@netconsult.ch
 X.400: S=romaguera;O=netconsult;PRMD=SWITCH;ADMD=ARCOM;C=CH;
 The Task Force as a whole can be reached per e-mail at the
 address:
 RFC 822: tf-88@SURFnet.nl
 X.400:   S=tf-88;O=SURFnet;PRMD=surf;ADMD=400net;C=nl;

RARE WG-MSG Task Force 88 [Page 44]

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