Troubleshooting TCP performance tutorial

Tim Eberhard xmin0s at
Sat Sep 18 01:00:49 UTC 2010

To add on to that. Recently Wireshark Network Analysis was released. It's an
excellent book covering wireshark and reading packet captures in general by
Laura Chappell. I just finished reading it and I have to say it's an
excellent book. Highly recommended.

Between those two books I think you'll be very close to being a
wireshark/packet capture guru.

I hope this helps,
-Tim Eberhard

On Fri, Sep 17, 2010 at 7:33 PM, Joe Hamelin <joe at> wrote:

> In a situation like yours I found Internet Core Protocols: The
> Definitive Guide by Eric Hall an easy to read guide to insuring that
> what you are seeing via wireshark.  I was able to find an issue with
> the DF bit in a load balancer that was causing confounding headaches
> in a network using wireshark and this book.
> Walk it through the syn-ack dance and don't trust that the devices are
> handling it correctly. Start at one end and work your way through and
> insure to YOUR satisfaction that every device proscribes to the
> protocol.  Don't rush, don't jump to conclusions.  Just follow the
> packet.  That's the best advice I can give you.
> --
> Joe Hamelin, W7COM, Tulalip, WA, 360-474-7474
> On Fri, Sep 17, 2010 at 5:06 PM, Abel Alejandro
> <aalejandro at> 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.
> >
> >
> >
> >
> >

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