Simulate a degraded QoS?

azaghul

Hi,

Probably an odd request...

I'd like to experiment as see what a poor QoS is like, is there any way to inject delay, jitter or packet loss into a simulated WAN link? Lack of bandwidth is easy enough to simulate (which would do packet loss as well), but the rest?

I'm currently using a 1760 as my frame-relay switch, which I'm sure would be the best injection point.

Any ideas?

pitviper

Not odd at all.

If you have PCs on both LANs, check out the free command line tool iperf (or jperf, the graphical front end but it has limited functionality). I use a single machine with multiple NICs and VMWare for the hosts. Set the WAN links to something like 384k and open up a ton of data streams w/iperf. You should be able to kill your call in no time. Hit the little blue "?" twice on the phone to see call/network statistics. You can also mark DSCP values w/iperf to simulate various other types of traffic to test your QoS policies.

azaghul

Thanks for the info. I used iperf briefly in the past, but talking typical desktop users into running it as a client can be "challenging". Should be easier in a home lab, especially with a GUI.