To clarify the point I want to make: - Certainly, there is currently no mechanism that allows you to limit a node on a broadcast link to a subset of all on-link prefixes (even though loss of RAs may temporarily prevent the node from seeing all on-link prefixes).
- The prefix-per-MN approach would be the first mechanism that guarantees to permanently limit a node on a broadcast link to a subset of all on-link prefixes. From this perspective, the prefix-per-MN approach does make a difference. - But my point is that things won't break if you use the prefix-per-MN approach on a broadcast link, because the IPv4/IPv6 architecture does AFAICT not require nodes to be aware of all on-link prefixes. Neighboring nodes will simply not be able to communicate directly on the link layer because they don't consider each other "on link". This is what we'd like to have in NETLMM anyway. - Christian -- Christian Vogt, Institute of Telematics, Universitaet Karlsruhe (TH) www.tm.uka.de/~chvogt/pubkey/ "Everything should be made as simple as possible, but not simpler." (Albert Einstein) Christian Vogt wrote: > Hi Julien, > > I don't think there is a problem. > > If you use the prefix-per-MN case on a broadcast link, what you get is a > link comprising multiple subnets. RFC 3513 explicitly allows links with > multiple prefixes: > > Currently IPv6 continues the IPv4 model that a subnet prefix is > associated with one link. Multiple subnet prefixes may be assigned > to the same link. > > (This is, BTW, the passage that Dave Thaler cites in > [draft-thaler-intarea-multilink-subnet-issues].) > > In the scenario you describe (the one including MNs A, B, and C), you > simply have a link with 3 prefixes. The unusual, but still legitimate > circumstance in this scenario is that the MNs do not see their > neighbors' prefixes. > > Note that a situation where hosts on the same link see different > prefixes may also arise when the link has multiple routers, each router > advertises a different set of prefixes, and no two hosts receive RAs > from the same router due to packet loss. The hosts will then not be > aware of their neighbors' prefixes. Certainly, this is unlikely to > happen, but it may happen. > > Let me know if I have missed something. > > - Christian _______________________________________________ Int-area mailing list [email protected] https://www1.ietf.org/mailman/listinfo/int-area
