On Oct 10, 2011, at 2:43 PM, Erik Nordmark wrote: > On 10/9/11 3:38 PM, Ole Troan wrote: >> Erik, et al, >> >> to expand on the ideas I presented on MLSR (or rather MLSRv2 as it hasn't >> really been described anywhere) as a method for numbering a routed home. >> please let me be clear that I'm not convinced this is a good idea. i.e. why >> not just get< /64? >> I do think we could get something working though. >> >> routers can be in an arbitrary topology. all routers running a routing >> protocol. >> the site prefix (/64) is either advertised in the IGP with a new LSA or >> proxying of RA messages is done (split horizon). >> a router advertises the same /64 prefix (in a PIO) on all of its interfaces. >> L bit is 0. >> >> the link model here is that all hosts are off link from each other. >> link-local scope is restricted to only the physical link. multicast >> link-local scope as well. > > And I assume the routers would pass around /128 routes for the hosts in the > home, and would automatically inject such a route when the SAVI-style table > learns about a new address. > Are those assumptions correct? > >> a host uses SLAAC (or DHCP) to create an address, then does DAD as normal. >> the first hop router uses it's routing topology database >> to check for conflicts. similar mechanisms described in SAVI are used to >> glean address information from the host. the SAVI binding >> database is then used to inject host routes into the IGP. > > What happens when the router crashes - does it loose its SAVI-style table? > Does it keep it in stable storage? > > If it looses it, then nobody would know on what link the hosts are, since the > hosts aren't required to periodically send any announcement to the routers. > > What happens when a packet arrives for an IP address that is in the /64 > prefix for the home, but there is no /128 route for it? Flood everywhere? > Drop? > > We looked that this when we worked on 6lowpan-nd, and concluded that by doing > explicit registrations from hosts to routers (the Address Registration > Option) with a lifetime we can make such networks work well without requiring > stable storage.
I heard a lot about stable storage being a requirement for a homenet router... and not much objection from the vendor reps. Perhaps that is a difference between homenet and lowpan. - Mark > > But that implies a host change. > > Erik > >> this requires no flooding of ND, or any other changes to on-link protocols >> for loop detection. no changes in hosts either. >> only downside is that it requires a host to have sent a packet of some form >> for the SAVI binding to be initiated. >> it might also be possible to support host mobility with the home with this >> mechanism. >> >> cheers, >> Ole >> > > _______________________________________________ > homenet mailing list > [email protected] > https://www.ietf.org/mailman/listinfo/homenet _______________________________________________ homenet mailing list [email protected] https://www.ietf.org/mailman/listinfo/homenet
