TWT - Comcast congestion

Tue Nov 30 19:45:53 UTC 2010

> Date: Tue, 30 Nov 2010 00:29:31 -0500 (EST)
> From: Jon Lewis <jlewis at lewis.org>
> 
> Anyone else seeing this or know the cause?
> 
>   5:  ash1-pr2-xe-2-3-0-0.us.twtelecom.net (66.192.244.214)  29.758ms
>   6:  pos-3-11-0-0-cr01.ashburn.va.ibone.comcast.net (68.86.86.145) asymm 11 846.582ms
>   7:  pos-1-7-0-0-cr01.atlanta.ga.ibone.comcast.net (68.86.87.86) asymm  8 866.718ms
>   8:  pos-1-11-0-0-cr01.dallas.tx.ibone.comcast.net (68.86.85.221) asymm 10 879.171ms
>   9:  pos-0-11-0-0-cr01.losangeles.ca.ibone.comcast.net (68.86.87.37) asymm 11 925.695ms
> 10:  pos-0-12-0-0-cr01.sacramento.ca.ibone.comcast.net (68.86.86.5) asymm 14 919.159ms
> 
> We opened a ticket with TWT and were told we weren't the first to report 
> the issue, but there was no ETR.  I adjusted our routing to depreference 
> TWT for reaching AS7922...which is kind of funny because Comcast clearly 
> doesn't seem to want traffic via the route we're now sending it.
> 
> 3356 7922 7922 7922
> 
> Don't want traffic via Level3...but can't take it via TWT?..I'll send it 
> to you over Level3.  At least that path works.

We have seen the same thing with other carriers. As far as I can see,
Comcast is congested, at least at Equinix in San Jose. Since this is all
over private connections (at least in our case), the fabric is not an
issue.

Maybe they will be using the money from Level(3) to increase capacity on
the peerings with the transit providers. (Or maybe not.)
-- 
R. Kevin Oberman, Network Engineer
Energy Sciences Network (ESnet)
Ernest O. Lawrence Berkeley National Laboratory (Berkeley Lab)
E-mail: oberman at es.net			Phone: +1 510 486-8634
Key fingerprint:059B 2DDF 031C 9BA3 14A4  EADA 927D EBB3 987B 3751