Cogent latency / congestion

Date: Mon, 20 Aug 2007 16:11:44 -0400
From: Mike Tancsa <>

>We're going crazy up here, I'm trying to nail down where exactly the
>problem is - We don't use Cogent anywhere, but we're having terrible
>problems with Bell and many sites in Europe...

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 from a site in Toronto (source
IP in AS577) back to me peering with Cogent's router in Toronto...
Toronto, Chicago, Kansas, Texas, Washington, Boston, Albany,
Toronto. Thats quite the milk run. Usually its Toronto, Chicago, Toronto.

Almost certainly the fiber cut of last night. Still down after >19
hours. Not a pretty picture for those lacking diversity between Chicago
and points east.