On Fri, 8 Nov 1996, Marten Terpstra wrote:
Ed Morin <edm@halcyon.com> writes
* Why doesn't BGP pick the link with the highest bandwidth, or, better * yet, pick the link with the highest bandwidth AND least congestion to * label as the "best" available route? The needed information is avail-
The first one is easy, in fact you can do that yourself by fiddling with metrics or such on the different BGP sessions. The second one would have dramatic consequences in terms of route instability. You pick one route now because of load on the link, the load changes and you pick the other, now BGP will have to change the announcement of this network to other peers. So, now we not only have flaps because of links/routers going up and down, we also have flap because of load changes on the network. The result: you are dampened out forever, or the network falls over.
Is this really true? All I'm asking for is that the route a router considers to be "best" be picked by something a little more rational than the ordinate order of its IP address relative to another link. I don't see a flap situation at all here -- only that a decision to route a packet may change more frequently based on load. Ed Morin Northwest Nexus Inc. (206) 455-3505 (voice) Professional Internet Services edm@nwnexus.WA.COM