CA> Date: Wed, 15 Feb 2006 14:04:24 -0600 CA> From: Chris Adams CA> There's a difference: computers (routers) handle the O(N^2) routing CA> problem, while people would have to handle the O(N^2) cooperative AS CA> problem. 0.1 ^ 2 < 5000 One must also consider the scalar coefficient. CA> We are a relatively small ISP with just a handful of multihoming Sounds like the O(N^2) coefficient is small. CA> customers. However, no two of them have the same other provider. What CA> is gained by us setting up relationships with a bunch of other providers CA> and getting special ASes assigned? What if one of those customers gets Each one needs an ASN, anyhow. CA> a connection to a third upstream, or if they change their upstream? Third upstream? They're ready for their own portable ASN. Change upstream? In general, change ASN. Slight pain, but not too bad for the average small leaf. If they're the only entity that uses both you and Joe-Bob's Inet, the coop ASN could still be used when they drop Joe-Bob and replace it with SomeOtherNet. CA> Right now, it doesn't affect us (we don't have to do anything), but in CA> your setup, it would require us to get yet another AS. It does affect you now. You add a BGP session to their portable ASN. Instead, you'd add a new ASN when the other upstream was one with whom you were not already cooperating. CA> Only one of our multihoming customers has a connection to someone we CA> already have a connection with, so there's no path between our network CA> and the rest. Again, this is the big rub. :-( Ideally, everyone would peer via an exchange point, or perhaps a local frame or ATM cloud. I'm more than a little hesitant to suggest shared upstreams leaking long prefixes between the lot of you, or anything else that even smells like a VPN. However, for every entity that multihomes between you and SomeOtherNet, there are probably a hundred with the SBC/Cox combination. Eddy -- Everquick Internet - http://www.everquick.net/ A division of Brotsman & Dreger, Inc. - http://www.brotsman.com/ Bandwidth, consulting, e-commerce, hosting, and network building Phone: +1 785 865 5885 Lawrence and [inter]national Phone: +1 316 794 8922 Wichita ________________________________________________________________________ DO NOT send mail to the following addresses: davidc@brics.com -*- jfconmaapaq@intc.net -*- sam@everquick.net Sending mail to spambait addresses is a great way to get blocked. Ditto for broken OOO autoresponders and foolish AV software backscatter.