Comcast problems?

Michael Sinatra michael at rancid.berkeley.edu
Sat Apr 5 19:40:24 UTC 2008


Ted Fischer wrote:
> 
> I didn't save any of my Wireshark traces, but this is what I observed 
> (I'm behind Charter at home but visiting my brother in NJ - Comcast 
> territory).
> 
> All attempts to check my e-mail (neither Charter nor Comcast) showed the 
> syns going out but no syn acks coming back.  Then, after a few minutes 
> (pop server time outs I guess) I started seeing fins coming back from 
> the pop server that matched my connection requests.  Saw that occur with 
> various http connection attempts as well.
> 
> Of course, the only reason I can send this reply out is that they appear 
> to be back up.  Any chance of getting a non-nonsensical RFO from someone?

TCP performance on my Comcast connection in the Bay Area was horrible 
last night.  tcpdump showed lost segments, dup acks, etc.  Moreover, the 
UDP traceroute I did showed high packet loss, with outbound traffic from 
my connection draining to ATT (AS7012) immediately upstream.  Today, the 
performance is much better, with traffic draining to Level(3)(AS3356) 
and no ATT in the picture.

michael





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