CURRENT_MEETING_REPORT_ Reported by Dino Farinacci/cisco Systems MOSPF Minutes The Multicast Extensions to OSPF Working Group met Thursday, August 1, at the Atlanta IETF. The meeting Agenda was: o Introductions, roster, assign note taker. o Progress of draft. o Review of July draft. o Progress of implementation. o OSIfication of specification. o Multicast scoping. Progress of Draft. John Moy (author of spec), felt the specification was ready for protocol review but not quite ready to implement from. The following are missing sections: o System requirements. (i.e., manipulating multicast filters in media controllers). o Data structures. o Detailed description for forwarding multicast datagrams. o Detailed description for forwarding cache construction. o Additions to base OSPF specification. - How to flood group-membership LSAs. - Database Description process with new option bits. - Generation of Summary LSAs. Review of July Draft. Changes from previous draft (distributed at St. Louis IETF) included: o Added concept of a ``Inter-area multicast forwarder''. The reason for this is that all ABRs do not need to forward multicast traffic. o Inter-AS multicast section is new. o Requirements on Inter-AS protocol are identified. Must determine 1 if a multicast datagram came from outside of AS or from its own AS going outside. o Reverse costs will be used for inter-area and inter-AS multicasting. John Moy described a scenario where problems will occur when reverse costs are used (in the case of the above bullet) in combination with forward costs used inside an area. It was determined that the problem can be corrected if reverse costs are used everywhere. Progress of Implementations. Initially there will be two implementations from Proteon and public domain source gated (Cornell). Steve Deering, from Xerox, is working on modifications to the BSD Unix kernel for forwarding multicast datagrams. He briefly described the data structure for the forwarding cache. The key to access the cache is based on the tuple (source network, destination group, TOS). OSIfication of Specification. Steve Deering presented IP multicasting to the ANSI X3S3.3 committee. The group is interested to use this research for OSI multicasting but no work has begun. Multicast Scoping. o TTL is used in multicasting to limit scope. The problem with TTL usage is that it does not take into account administrative boundaries. o Scope should be based on the group address. o It was noted that the first 256 assigned multicast addresses are meant for local wire only. o Scott Brim, from Cornell, has proposed to provide scoping in IGMP. o Scoping boundaries should have multiple levels. For example, (Site, AS, Country, Continent). Attendees Jim Beers beers@nr-tech.cit.cornell.edu Scott Brim swb@nr-tech.cit.cornell.edu Chi Chu chi@sparta.com Richard Colella colella@osi3.ncsl.nist.gov Steve Deering deering@xerox.com Dino Farinacci dino@cisco.com 2 Dennis Ferguson dennis@canet.ca Robert Griffioen rgriff@bnr.ca Jeffrey Honig jch@nr-tech.cit.cornell.edu Phani Jujjavarapu phani@cisco.com April Merrill abmerri@tycho.ncsc.mil Greg Minshall minshall@wc.novell.com John Moy jmoy@proteon.com Karen O'Donoghue kodonog@relay.nswc.navy.mil Bob Stewart rlstewart@eng.xyplex.com David Waitzman djw@bbn.com Robert Woodburn woody@cseic.saic.com L. Michele Wright uncng!michele@uunet.uu.net Osmund de Souza desouza@osdpc.ho.att.com 3