From: Mark Knopper To: Date: Tue, 16 Jul 2002 04:00:49 -0400 Subject: draft ptomaine minutes Hi. Here are draft minutes of the Ptomaine meeting. Thanks to Sean McCreary for being Official Scribe, and to Hal Peterson for unofficial notes. Please note item 2(a) below, and send comments to the list on the IPv6 EC issue for the redist-communities draft. Also please send any corrections or comments. Mark ====== Prefix Taxonomy Ongoing Measurement & Inter Network Experiment (ptomaine) - Minutes Agenda slides here: http://bgp.nu/~mak/ptomaine_yokohama.ppt http://bgp.nu/~mak/ptomaine_yokohama.pdf TUESDAY, July 16 at 1300-1400 Room 503 ======================================= CO-CHAIRS: Sean Doran [not present] Mark Knopper AGENDA: 1. Administrivia 7 minutes General Discussion: ptomaine@shrubbery.net To Subscribe: majordomo@shrubbery.net In Body: subscribe ptomaine Archive: http://www.shrubbery.net/ptomaine Scribe? [Thanks to Sean McCreary.] Blue Sheets Agenda Bashing 2. Discuss Working Group Drafts: a. draft-ietf-ptomaine-bgp-redistribution-00.txt (15 mins - O. Bonaventure et. al.) Andrew Lange on representing IPv6 in redistribution communities. Problem is that there isn't enough space in the 64-bit EC value to represent 128-bit IPv6 addresses. Andrew proposes variable-length ECs. This is a proposal to modify extended communities set to have: one octet length field variable length data field eliminating regular type force all communities to have type and subtype type defines format of data field subtype would provide clarification of interpretation He will send email to IDR list with detailed proposal. He proposes to hold this ptomaine draft until it can be updated with the final EC solution. Hal Peterson: Changing syntax and semantics of extended communities out of scope. What we have now solves existing problems, so we should proceed rather than waiting for IDR to approve changes to extended communities. There was no consensus to these opposing viewpoints, and document authors were not present. Therefore we will take the discussion to the mailing list. > Question on list: what about convergence time impact of redist > communities? Mark asks for information, but does not see need to hold > draft for it. > > Also on the list, somebody suggested adding a wildcard for `always add > NO_EXPORT'. > > tbarron: concern about community pollution; it is a valuable feature > of the proposal that redist community is defined as nontransitive. > That is value above and beyond the codification of existing practice. Andrew Lange: `pollution' of routing table with excessive communities is a configuration error, the example presented at NANOG will be cleaned up by stripping communities at their ISP's boundary b. draft-ietf-ptomaine-nopeer-00.txt (10 mins - Geoff Huston) Consensus by hum (and approval by Randy as AD) to progress this document as BCP. IANA considerations (to reserve a well-known community value) can go forward in a BCP. Mark will issue last call on list. 3. Presentation on BGP trends (20 mins - Cengiz A. ) Slides can (currently) be found here: http://bgp.nu/~mak/cengiz.pdf Cengiz Alaettinoglu presented `Recent BGP Trends', an update of the talk he gave at the London IETF The data was from RIPE/RIS, containing all BGP messages not just table snapshots Time period: Dec 2000 - July 2002 Routing table growth rate has slowed dramatically, both in absolute slope and in big-Oh. `Historic' prefixes: classful prefixes that are usually replaced by a covering CIDR aggregate prefix in the core routing table Without CIDR, routing table would be 5x larger to hold all the `historic' prefixes Growth rate in historic prefixes is slowing Cengiz suggests this indicates new advertisements are not appearing in the core table due to a preexisting covering aggregate prefix? Cengiz' taxonomy of prefixes: Multi-homing Engineered prefixes Punching holes Regular prefixes Number of engineered and hole prefixes have decreased Number of multihomed prefixes with multiple origins not growing BGP churn per router: last year churn was slightly decreasing Trend has continued churn per prefix decreasing even faster So overall stability is improving, total variability decreasing Most churn (>75%) was from peering loss This continues to be a problem, although the collected uptime data is for multihop peerings, which are likely to be less stable than conventional ones Summary: Table growing BGP churn decreasing, decelerating engineered prefixes no longer churn more than their share peering loss/reestablishment still a problem Geoff: do you differentiate between advertisements/withdrawals and path changes Path changes are becoming more stable, but withdrawal numbers increased substantially in April 2002 This may have to do with large-scale changes in the core, with the demise of some carriers. Dan Massey presented a graph of BGP message classification from RIPE/RIS data Randy Bush: 95% of the session resets are due to measurement artifacts (EBGP multihop) rather than real problems Dan: We don't see session resets from non-multihop peerings either Geoff's graphs can be found at http://bgp.potaroo.net Randy, Mark and others called for others to post any current BGP measurements or analysis to the ptomaine list. 4. Charter review & call for contributions (8 mins) Mark revisited the charter: This working group has a role to play, but doesn't have any outstanding standardization issues to discuss Last milestone in the charter was dated FEB 02 If no more documents are submitted, then working group should go dormant in a month Questioner: Ptomaine has been a useful forum for measurement presentations like Geoff's. Randy (AD) agreed. Mark: Ptomaine fills a role like the CIDR deployment working group did David Ward: One month is too short an interval to close down the working group It would be better to just not meet for awhile, but keep the mailing list and the working group open Ed Kern: You could always just consider a recharter. That could take more than a year.