Friends, Below you find a summary of the IAB (now called Internet *Architecture* Board after moving under the wings of the Internet Society) proposals in response to the ROAD group work which we discussed at the last RIPE meeting. Personally I think that this is a very sound proposal and that RIPE should endorse it. Discussion welcome. Daniel ------- Forwarded Message Date: Wed, 1 Jul 92 19:55:36 EDT From: "Lyman Chapin" <lyman@BBN.COM> Subject: IAB proposals for CIDR and IPv7 A summary of the IAB's proposals in response to the work of the ROAD group. ------------------------------------------------------------------------ During its meeting in Kobe, Japan on June 18 and 19, the IAB reviewed the draft report of the ROAD group concerning the problems of "running out of IP network numbers" and "Internet routing table size explosion", and a companion report from the IESG of "IESG Deliberations on Routing and Addressing". The IAB's analysis of the many possibilities suggested by these two reports led it to the following conclusions, which are docu- mented in an internet-draft entitled "IP Version 7": 1) The ROAD group's work, compiled over a period of four months, makes it very clear that the problems of too few IP addresses and too many Internet routes are real and immediate, and represent a clear and present danger to the future successful growth of the worldwide Internet. The IAB was therefore unable to agree with the IESG recommendation to pursue an additional six-month program of further analysis before deciding on a plan for dealing with the ROAD problems. The detailed design, engineering, and deployment work must begin now, and it is therefore imperative that the efforts of the Internet community be focussed on a common goal. 2) The IETF should aggresively pursue the work to engineer CIDR ("classless inter-domain routing", described in RFC 1338), including the extensions to the inter-AD routing protocols to support variable-length masks/prefixes, and the associated address administration paradigm. 3) Since CIDR postpones, but does not prevent, the eventual exhaustion of the 32-bit IP address space, the IETF should also aggressively pursue a detailed technical and organizational plan for using CLNP (the OSI internetwork protocol defined by the ISO 8473 standard, which uses 160-bit addresses) as the basis for a new version of IP (which we have dubbed "IP version 7"), succeeding over time the current version of IP (version 4) in the Internet. An initial description of how CLNP could be used for this purpose within the current TCP/IP architecture and with the existing Internet applications is described in RFC 1347. 4) CLNP has larger addresses than IP, but like IP it lacks features that are expected to be necessary to support future Internet appli- cations and services. The IAB therefore also encourages the pursuit of research in areas such as policy-based routing, route preallocation and cacheing, and deterministic end-to-end QOS mainten- ance (for real-time and other delay-variance sensitive traffic). It is important to understand that (3) above does NOT mean "adopting OSI" or "migrating to OSI" or "converting the Internet to use GOSIP protocols". The IAB recommends only that a new version of IP (IPv7), with much wider addresses and a more extensible header, be based on the existing CLNP. IPv7 is intended to be deployed within the current Internet TCP/IP architecture, not as part of an "OSI stack". There are, of course, many issues that must be resolved before CIDR and IPv7 can actually be deployed in the operational Internet. No one should imagine that there is not still a great deal of work to be done, notwith- standing the efforts that have already been expended by several of the IETF working groups and by the members of the ROAD group over the past year. In recommending that the ROAD problems be addressed by a combination of CIDR, IPv7, and further research, the IAB has deliberately chosen NOT to recommend any of the possible alternatives, so as to present a single focal point for the community consisting of what we believe to be the best technical solutions to the problems. This should not be construed as a blanket "condemnation" of the alternative proposals that have been floated in various parts of the IETF. However, we believe that the normal IETF process of "let a thousand [proposals] bloom", in which the "right choice" emerges gradually and naturally from a dialectic of deployment and experimentation, would in this case expose the community to too great a risk that the Internet will drown in its own explosive success before the process had run its course. The IAB does not take this step lightly, nor without regard for the Internet traditions that are unavoidably offended by it. We look forward to a lively discussion of these conclusions during the upcoming IETF meeting in Boston. - Lyman Chapin IAB chair ------- End of Forwarded Message