RFC 1615 (rfc1615) - Page 2 of 17

Migrating from X

RFC 1615         Migrating from X.400(84) to X.400(88)          May 1994


   Appendix D - Abbreviations                                       16
   Authors' Addresses                                               17

1. New Functionality

   Apart from the greater maturity of the standard and the fact that it
   makes proper use of the Presentation Layer, the principal features of
   most use to the European R&D world in X.400(88) not contained in
   X.400(84) are:

    - 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 nondelivery
      reports. The current endemic use of DLs in the research
      community makes this a fundamental requirement.

    - The Message Store (MS) and its associated protocol, P7. The
      Message Store provides a server for remote User Agents (UAs)
      on Workstations and PCs enabling messages to be held for
      their recipient, solving the problems of non-continuous
      availability and variability of network addresses of such
      UAs. It provides powerful selection mechanisms allowing the
      user to select messages from the store to be transferred to
      the workstation/PC. This facility is not catered for
      adequately by the P3 protocol of X.400(84) and provides a
      major incentive for transition.

    - Use of X.500 Directories. 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 provision of message Security services including
      authentication, confidentiality, integrity and non-
      repudiation as well as secure access between MHS components
      may be important for a section of the research community.

    - Redirection of messages, both by the recipient if
      temporarily unable to receive them, and by the originator in
      the event of failure to deliver to the intended recipient.

    - Use of additional message body encodings such as ISO 8613
      ODA (Office Document Architecture) reformattable documents or
      proprietary word processor formats.






Houttuin & Craigie