Date: Sun, 16 Dec 2001 17:28:30 -0800 (PST) From: David Barak <thegameiam@yahoo.com>
AS 701 always announces the best route, as their routers know it. Their average AS-path length is
This is silly. Local-pref is one of the methods by which a router learns the "best route". The question was: If not by local-pref, then by what?
under 2, so it doesn't seem to be a problem. If a
And if someone pads their adverts to 701 at their egress? Suddenly the "best route" to the downstream is via the peer. Sorry, it doesn't matter if "average as-path length is under 2" or not... the point is that (unless BGP weight comes into play), after reachability, as-path length is the first route selection mechanism after reachability.
customer of AS 701 wants to insure that his/her route is advertised in all cases, s/he could send a community which AS701 edge devices could use to manipulate local-preference upward. [this was covered
IOW, the bottom line answer is: reliance on as-path length, but local-pref is tunable via communities. Eddy --------------------------------------------------------------------------- Brotsman & Dreger, Inc. - EverQuick Internet Division Phone: +1 (316) 794-8922 Wichita/(Inter)national Phone: +1 (785) 865-5885 Lawrence --------------------------------------------------------------------------- Date: Mon, 21 May 2001 11:23:58 +0000 (GMT) From: A Trap <blacklist@brics.com> To: blacklist@brics.com Subject: Please ignore this portion of my mail signature. These last few lines are a trap for address-harvesting spambots. Do NOT send mail to <blacklist@brics.com>, or you are likely to be blocked.