I have just installed PP to try and trouble shoot a wireless LAN (which, btw is accessing the Internet via a wireless IPS).

Here's the scoop:

from the command prompt, if I ping my website at work I get an average ping time of 186ms, with most appearing under 200ms.

from the same machine, same network, but using PingPlotter, I'm getting average ping times of 450ms with a lot hitting or exceeding 500ms.

Why the big difference in times?

I've tried trimming the packet size down to 32 bytes to match the ping packet size - I even trimmed it down to 28 (the smallest size apparently recommended).

It might be because of the number of concurrent outstanding requests. TRACERT and PING only do one packet at a time, while PingPlotter sends out multiple concurrent packets.

This means that PingPlotter might be sending out more packets than your bandwidth can handle, or possibly that a router between you and the final destination is downprioritizing because it sees a number of packets.

An easy way to check if this is the problem is to change your trace interval to 30 seconds, and then change your "Time interval between hop traces" to something high enough that there is no overlap - in your case, I recmmend using "750" for the initial attempt.

If you get a significant change in performance by modifying these numbers, then you might try backing this number down to something smaller until you start to see latencies being affected. This will probably start to happen when this number gets < 100 ms.

The big caveat of increasing this number is that PingPlotter's really fast response times will begin to take a bit longer.

If this doesn't change things, try changing PingPlotter to "Ping Only" mode, by using the "View -> Ignore first hop(s)" menu. Set this to "Ping final hop only". This will remove all intermediate hop information, but will make PingPlotter work more closely to the "PING" command.

A last thing to try is to change the packet cargo, but this is an unlikely contributor based on the information you shared here.

Try changing the interval between hop traces and then let us know if this makes a difference - we'll try to help you "tweak" your parameters to get good performance.

- Pete