jitter testing

[markus sesser <markus () sesser eu>]

Hi,

Do anybody know how to measure delay variation (jitter) in layer2/3 
networks?
I'm looking for system- or freeware-tools to do this (no commercial tools!).

What about normal ping test?
1000 packets transmitted, 1000 received, 0% packet loss, time 9016ms
rtt min/avg/max/mdev = 0.194/0.207/0.326/0.015 ms
--> jitter should be 0.326 - 0.194 = 0.132 ?!?

other suggestions?

thanks,
markus