On Tue, Oct 09, 2001 at 07:19:35AM -0700, Randy Bush wrote:
We are talking about different types of multihoming. I mean simple multihoming situation when all multihomed customer's needs in routing are covered by they upstream providers routing policies. ^ note the use of plural above. now read rfc 1930.
Randy, rfc1930 consists of 563 lines. I suppose you are talking about:
I think it's far simpler than that. Quoting (and guessing): To rephrase succinctly: An AS is a connected group of one or more IP prefixes run by one or more network operators which has a SINGLE and CLEARLY DEFINED routing policy. I.e. a provider (an AS) can only have a single routing policy. However, I also sense some language confusion above, and that what you're trying to say is actually "a simple multihoming situation where any one of the multiple uptstream providers' routing policy would be adequate for the client in question" However, I don't agree that it's a good idea to willfully cause the number of routes originated from different source ASes to increase. Furthermore, the routing complexity doesn't really rise as a function of the number of ASes -- it's rather the number of prefixes or perhaps rather the number of unique paths available which causes the entropy increase in the default-free zone which scares some of us. In the bigger picture it doesn't really make any difference whether the more- specific route comes from PI or PA space or whether the route is consistently originated from a new AS or (shudder) separately from the two (or more) upstream providers; the entrypy increase in the default- free zone would be the same either way. Regards, - Håvard