Wireshark-users: [Wireshark-users] Question on Internet Performance Troubleshooting

From: "Small, James" <JSmall@xxxxxxxxxxxx>
Date: Fri, 2 Mar 2007 11:51:19 -0500

Hello,

Recently while installing a firewall for someone, I noticed that the
firewall seemed to cause/exacerbate Internet performance issues.  There
were some issues even without the firewall, but the firewall definitely
made the issues significantly worse.

Of course I used Wireshark to perform a whole bunch of captures but I
could not figure out anything definitive.

I did notice that when I had a "problem" connection which would exhibit
erratic throughput (for example, an http download), that there seemed to
be a fairly high number of duplicate acks/retransmissions/out of order
packets - around 10%.

My question is - for trying to monitor/isolate/troubleshoot network
performance problems, are there any addition ways I can leverage
Wireshark or use complimentary tools?

What about simulation?  Would anyone recommend something like this to
help?  If so, could you recommend a tool to use in concert with
Wireshark?

Thanks,
  --Jim