Op 7 nov. 2012, om 23:33 heeft Ole Troan (otroan) het volgende geschreven:
> > > On 7 Nov 2012, at 14:50, "Teco Boot" <t...@inf-net.nl> wrote: > >> This should be in the homenet-arch, I think. >> >> It sounds so obvious to me, that I described this in a short text in BRDP: >> A Router should request a prefix for attached subnetworks, with >> DHCP-PD [RFC3633], where there is at that moment no on-link prefix >> for a selected Border Router. >> >> I could make the should a MUST. > > Disagree. Hierarchical or flat PD (with relays) don't work for multihomed > sites, have problems with arbitrary topplogies etc. I do not suggest hierarchical PD, nor flat PD with relays. Leaves open flat PD without relay. Can you explain why this doesn't work? My thoughts were driving me to a more manageable situation, where the CPE router manages all delegated prefixes for that ISP. CPE router can be multi-homed, then the task is for each ISP. HW for deterministic prefix configuration can be implemented on CPE router, or somewhere on ISPs network. For ULA, one router is to be elected as "homenet manager". Here, a more distributed approach could make sense. Still I think management of such is unneeded complex and adds unneeded HW requirements on all routers (need for non-volatile memory, for deterministic behavior). Related topic: IMHO non-CPE routers need a configuration for relaying DHCP requests to the CPE routers. PD from CPE router doesn't add complexity. Teco > > Cheers, > Ole > > >> >> Teco >> >> Op 7 nov. 2012, om 16:46 heeft Ted Lemon het volgende geschreven: >> >>> I don't have a particular preference for DHCP-PD over OSPF in homenets, but >>> I just wanted to quickly contradict what's been said by several people at >>> the mic: that figuring out what prefix to delegate is hard. It's not >>> hard, actually―it's dead easy. The reason folks think it's hard is >>> because they're solving the wrong problem. >>> >>> The problem that needs to be solved is how we number each home subnet. >>> The answer to this question is, "with a /64." There is no other answer. >>> You never want to number a subnet with a /52. Therefore, the delegating >>> router should never delegate anything but a /64. Problem solved. >>> >>> I think the disconnect here is that people are thinking the routers to >>> which prefixes are delegated need to themselves be delegating routers, but >>> this is incorrect. What they need to do is _relay_ prefix delegation >>> requests to the delegating router from which they got their own delegation. >>> >>> This scales to multi-homing with multiple delegating routers―you just relay >>> every PD request upstream to all delegating routers. >>> >>> I'd be happy to write a draft that describes how this works if someone >>> actually wants it; I get the sense that people are pretty in love with the >>> OSPF solution and would prefer not to be distracted, and I have no argument >>> with that if that's the working group consensus. >>> >>> _______________________________________________ >>> homenet mailing list >>> homenet@ietf.org >>> https://www.ietf.org/mailman/listinfo/homenet >> >> _______________________________________________ >> homenet mailing list >> homenet@ietf.org >> https://www.ietf.org/mailman/listinfo/homenet _______________________________________________ homenet mailing list homenet@ietf.org https://www.ietf.org/mailman/listinfo/homenet
