Network Working Group                                           P. Gross
Request for Comments: 1719                                           MCI
Category: Informational                                    December 1994


                         A Direction for IPng

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.

Abstract

  This document was submitted to the IPng Area in response to RFC 1550.
  Publication of this document does not imply acceptance by the IPng
  Area of any ideas expressed within.  Comments should be submitted to
  the [email protected] mailing list.  This RFC specifies
  criteria related to mobility for consideration in design and
  selection of the Next Generation of IP.

Table of Contents

  1.   Introduction . . . . . . . . . . . . . . . . . . . . . . . . 1
  2.   A Direction for IPng . . . . . . . . . . . . . . . . . . . . 2
  3.   Issues Toward IPng Resolution. . . . . . . . . . . . . . . . 3
  4.   Security Considerations. . . . . . . . . . . . . . . . . . . 5
  5.   Author's Address . . . . . . . . . . . . . . . . . . . . . . 5

1. Introduction

  At the Amsterdam IETF meeting, we held a BOF, entitled the "IPDecide
  BOF", on the process and progress of the IPng activities.

  ("IPng" stands for "IP, the next generation".   The IPDecide BOF was
  chaired by Brian Carpenter.  Minutes are available in the IETF
  directories, with the file name </ietf/93jul/ipdecide-minutes-
  93jul.txt>.)

  The IPDecide BOF explored several facets of the IPng process, such
  as:

     "What is the basis for choosing the next generation IP (i.e., what
     are the technical requirements and decision criteria)."






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     "With the advent of CIDR and new, more stringent address
     assignment policies, are we comfortable that we truly understand
     the level of urgency?"

     "Should the IETF or the marketplace make the final IPng decision".

  The BOF was held in a productive atmosphere, but did not achieve what
  could be called a clear consensus among the assembled attendees.  In
  fact, despite its generally productive spirit, it did more to
  highlight the lack of a firm direction than to create it.

  The IPDecide BOF was followed the next evening by the open IESG
  plenary. During this session, the IESG and the assembled attendees
  discussed the IPng issues and seemed to arrive at a consensus based
  on the following set of bullets presented by the IETF chair:

     "The IETF needs to move toward closure on IPng."  That is, the
     IETF should take active steps toward a technical decision, rather
     than waiting for the "marketplace" to decide.

     "The IESG has the responsibility for developing an IPng
     recommendation for the Internet community."  That is, the IESG
     should provide leadership and take specific actions to help move
     the IETF toward a technical decision.

     "The procedures of the recommendation-making process should be
     open and published well in advance by the IESG."

     "As a part of the process, the IPng WGs may be given new
     milestones and other guidance to aid the IESG."

     "There should be ample opportunity for community comment prior to
     final IESG recommendation (e.g., there will be an extended Last
     Call)."

2. A Direction For IPng

  Building on this consensus, I'd like to announce a set of specific
  directions in the IESG that I hope will move us toward timely
  resolution of many of the key IPng issues.

  The IESG will establish a temporary, ad hoc, "area" to deal
  specifically with IPng  issues.  The charter for this new IESG area
  is to develop a recommendation on which, if any, of the current
  proposals should be adopted as the "next IP".  This recommendation
  will be submitted to the IESG and to the Internet community for
  review.  Following an adequate period of review to surface any
  community concerns, the IESG will issue a final IPng recommendation.



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  All of the current IPng-related working groups will be moved
  immediately into this new area.

  This new area will be headed by two co-Area Directors from within the
  IESG. I have asked Allison Mankin (NRL), current Transport Services
  AD, and Scott Bradner (Harvard), current Operational Requirements AD,
  to serve as co-AD's for this temporary area.  I am very pleased to
  report that they have agreed to take this important assignment.
  (Because this is expected to be a temporary assignment, Scott and
  Allison will also continue to serve in their current IESG positions
  during this period.)

  All IETF Areas are now expected to have Area Directorates.  For the
  IPng Area, a Directorate will be especially important to bring
  additional viewpoints into the process.  Therefore, I am asking that,
  as their first action, Scott and Allison form a specific IPng
  Directorate to act as a direction-setting and preliminary review
  body.  The IPng process will continue to be completely open, and
  therefore reports and meeting notes from any IPng Directorate
  meetings will be published in timely fashion.

3. Issues Toward IPng Resolution

  Two important issues need resolution immediately before we can expect
  progress toward an IPng recommendation:

     - What is the scope of the effort?

     That is, should IPng be limited to solving the well known scaling
     and address exhaustion issues; or should IPng also include
     advanced features such as resource reservation for real-time
     traffic?

     The argument in favor of considering advanced features is that
     migration to a new IP is (hopefully, only!) a once-in-a-generation
     occurrence, and therefore all advanced features should at least be
     considered.

     Arguments opposed to considering advanced features include the
     fact that we may not have time for this level of effort before the
     scaling and address exhaustion problems confront us, and that we
     may not have the necessary understanding and experience to make
     all the correct choices at this time.








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     - What is the available timeframe?

     That is, before we can even begin to make an informed decision
     about the scope, we need a better understanding of the urgency and
     time constraints facing us.

     Factors that affect the available time include the current rate of
     address assignments (which can give us an estimate of when we are
     currently projected to run out of addresses), the current policies
     governing address assignment (which can give us an understanding
     of how policies affect the assignment and utilization rates), the
     impact of CIDR aggregation, the development time for IPng, and the
     time needed to field and migrate to the new IPng.

  Therefore, I am asking the new AD's and the Directorate to start
  immediately the following specific activities to help guide their
  ultimate IPng recommendation:

     1. Develop an understanding of the available timeframe, covering
     at least the following issues:

        - Review Internet growth metrics, such as the current address
        assignment and utilization rates.  Develop an understanding of
        how the new address assignment policies impact the assignment
        and utilization rates.

        - Review the expected impact of CIDR address aggregation.
        Develop an understanding of the expected savings due to CIDR
        aggregation.

        - Develop new technical guidelines for classless Internet
        addressing.  Specific examples include guidelines for how to
        utilize variable length subnet masks, and how to utilize
        currently unused Class A and B addresses in a classless fashion
        in hosts and routers.

        - Develop a strong understanding of the time required for the
        development, fielding, and migration for a new IP.

        - Based on all the above issues,

           (a) develop an estimate for how long we have to develop
           and deploy an IPng.  This could be a set of estimates
           based on best/worst case estimates for how each of the
           above factors will affect the available timeframe.






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           (b) Consider whether more stringent assignment policies
           might provide additional time.  If so, recommend such
           policies.

           (c) make a recommendation on whether it is worthwhile to
           mount a serious effort to reclaim addresses and/or to
           renumber significant portions of the Internet.

     2. Based on an informed judgment of the time constraints above,
     make a recommendation regarding the scope for IPng, i.e., should
     IPng consider scaling issues only or advanced topics also.

     3. Based on the scope and time constraints, develop a clear and
     concise set of technical requirements and decision criteria for
     IPng.  These should include, but not be limited to, the criteria
     outlined in the IESG statement (RFC1380).

     4. Based on the decision criteria, scope, and time constraints,
     make a recommendation on which of the current IPng candidates to
     accept, if any.

     Finally, I am asking Scott and Allison to make a detailed report
     at the opening plenary of the next IETF meeting in November on the
     status of setting up their new area, and on their progress toward
     organizing the above work items.  In particular, the status of the
     work items on timeframe should be fully reported. This will be
     followed by regular progress reports to the Internet community, at
     IETF meetings and in other appropriate forums.

  Please join me in giving Scott and Allison our full cooperation, and
  in thanking them for accepting this daunting assignment.  I feel
  confident that we will now make significant progress on the important
  IPng issues facing the Internet community.

4. Security Considerations

  Security issues are not discussed in this memo.

5. Author's Address

  Phill Gross
  Director of Internet Engineering
  MCI Data Services Division
  2100 Reston Parkway FL 6
  Reston, VA   22091

  Phone: 703-715-7431
  EMail: [email protected]



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