[98836] in North American Network Operators' Group
Re: Cogent latency / congestion
daemon@ATHENA.MIT.EDU (Steve Gibbard)
Mon Aug 20 17:44:45 2007
Date: Mon, 20 Aug 2007 14:43:45 -0700 (PDT)
From: Steve Gibbard <scg@gibbard.org>
To: nanog@merit.edu
In-Reply-To: <200708202011.l7KKB6fL024641@lava.sentex.ca>
Errors-To: owner-nanog@merit.edu
On Mon, 20 Aug 2007, Mike Tancsa wrote:
> Bell uses Cogent in a large way. The second traceroute was from an IP in
> their AS (577) out. I am prepending out Cogent, but Bell does everything it
> can not to use Teleglobe so I am having problems influencing their routes to
> come back that way. They also have a very odd path out of Chicago. This is
Bear in mind that doing "everything they can not to use Teleglobe"
probably involves local preference. Local preference comes before AS path
length in the BGP selection order, so nothing you can do with prepending
is going to help. You'll need to either keep them from seeing the
undesirable path at all (drop the announcement, ask your upstreams to
limit its propagation, etc.) or convince Bell not to use it. Depending on
the setup, you may be able to limit route propagation with communities, or
it may require some phone calls.
-Steve
