WMM QoS fairness with Video streams

Live forum: http://rt2x00.serialmonkey.com/viewtopic.php?t=5606

qjantnn

10-09-2009 00:48:47

Hi !

I am testing WMM fairness by using linux + Edimax EW7318 together with another client.
My AP is configured for 5.5 MB of traffic, and I send approx 5MB from EW7318 and 5MB from the other client. I and sending UDP traffic with the same QoS priority in parallel from the two devices.

For BEST_EFFORT, BACKGROUND and VOICE I see that EW7318 and my other client get the same throughput (approx 2,5MB each).
When I send VIDEO-streams from both devices I see that EW7318 gets below 2 MB while the other client gets almost 4MB.
I did the same test with an Intel 3945 card (replaced EW7318) and then both VIDEO streams got the same throughput (approx 2,5 MB each).

I am running Fedora 11 (kernel 2.6.30.5) with the latest compat-wireless (2009-09-08).

Does anybody know how to debug this ?

IvD

10-09-2009 04:39:10

Can you try if configuring the WMM parameters (aifs, cwmin, cwmax) helps in improving the performance?
If think you can control those parameters with the 'iw' configuration tool.

qjantnn

10-09-2009 17:05:39

Did not find any way to set the WMM parameters with iw. Have downloaded latest iw-tarball (iw-0.9.17.tar)

Br /JT