Date: Fri, 17 Sep 2010 20:06:09 -0400 From: "Abel Alejandro" <aalejandro@worldnetpr.com>
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.
You might look at http://fasterdata.es.net. A lot of it is aimed at very large volume data transfers, but quite a bit is relevant to all TCP issues. -- R. Kevin Oberman, Network Engineer Energy Sciences Network (ESnet) Ernest O. Lawrence Berkeley National Laboratory (Berkeley Lab) E-mail: oberman@es.net Phone: +1 510 486-8634 Key fingerprint:059B 2DDF 031C 9BA3 14A4 EADA 927D EBB3 987B 3751