Troubleshooting TCP performance tutorial

Michael Painter tvhawaii at
Sat Sep 18 21:42:30 UTC 2010

Abel Alejandro wrote:
> Greetings,
> This past week I have been trying to find the root cause of tcp
> performance problems of a few clients that are using a third party metro
> Ethernet for transport. RFC2544 tests (Layer 2) and iperf using UDP give
> good symmetric performance almost 100% the speed of the circuit. However
> all kind of TCP tests result in some kind of asymmetrical deficiency,
> either the upstream or downstream of the client is hugely different. The
> latency is not a huge factor since all the metro Ethernet connections
> have less than 2 ms.
> So the question basically if is there a good tutorial or white paper for
> troubleshooting tcp with emphasis of using tools like Wireshark to debug
> and track this kind of problems.
> Regards,
> Abel.

It might be worth your while to run the analysis found here:

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