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Re: Nanog list uncharacteristically quiet?
> Sounds like this would make everything be symmetrically routed. No. It only means the end system's first hop is symmetrical. The intermediate systems might packet-stuff on multiple paths, or choose a different path based on private data, or whatever. My goal is not end to end path symmetry -- hot potato routing makes that impossible in any case. My goal is that an end system should be able to accept connections via multiple providers without needing a routing table from each of those providers. (Which can't be made symmetrical even in the average case, anyway.) > Has anyone researched whether this can scale? I havn't. I know that right now, someone who wants to multihome has to do way too much work and they cannot reliably send packets back on the same first-hop as the last-hop they came in on, which makes it pretty much worthless to multihome unless you break your BGP listener to use round robin or pseudo random path selection -- and when we did this it made some things worse rather than better. > Will you handle the case where the interface a flow uses changes > during the course of the flow? If the link (or ARP) for the current next-hop dies, the route rehomes among the remaining interface defaults and then rehomes again next time a segment is received on some remaining-up interface. > I assume this will lead to "round robin default" until an inbound > packet for the flow is received from a new interface. That's what I remember saying, yes. > Will the "round robin default" favor uncongested or highest speed links? Not initially. My test environment has a pair of 10baseT links and the congestion is all after the first hop, where interface statistcs can't help with local route selection. I won't entertain the above question seriously unless our initial results hint that it will be time well spent. > I can't wait to hear the results of doing this! I expect to have an informal report for this mailing list by January 10th. - - - - - - - - - - - - - - - - -