Re: TCP congestion

[Joe Loiacono <jloiacon () csc com>]

owner-nanog () merit edu wrote on 07/12/2007 02:07:00 PM:

> Typical Problem Scenario: Data transmission is humming along 
> consistently at 2 Mbps, all of a sudden transmission rates drop to 
> nothing then pickup again after 15-20 seconds. Prior to the drop off
> (based on packet capture) there is usually a DUP ACK/SACK coming 
> from the receiver followed by the Retransmits and congestion 
> avoidence. What is strange is there is nothing prior to the drop off
> that would be an impetus for congestion (no high BW utilization or 
> packet loss).

Perhaps you're filling buffers by flowing from a 1Gbps link into a 9Mbps 
circuit. Dropped packets induces slow-start/congestion avoidance.

Joe