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I am trying to make some tests on my Atheros card (3com, 11a/b/g Wireless card, 3CRPPAG175). I observed that for Voice and Video packets the band is divided by half. I expected that Voice will be threated with the highest priority and Video will be limited to the minimal value when the network is saturated. Could you advise where is the problem? In methodology or in the driver?

Some details about the env:

How it was tested:

  • sources had been downloaded and compiled
  • card had been configured to work as a AP, hostapd configured, wmm_enabled=1 in hostapd.conf file
  • to symulate the trafic in the network I am using nuttcp
  • on the computer which was connected to my wireles card I started the command: nuttcp -S -on my computer (AP) I limited the rate on the interface to 1M: iwconfig wlan1 rate 1M
  • to have few streams with different access category I run thye following command (in separate teminals to run it simultanously and observe the rate on the console output): nuttcp -il -v -u -c 40 -T 60 -p 5002 For each stream the port value had been changed to not duplicate them (-p parameter) For specify the traffic category i have been changing the 'c' parameter as follows: -c 8 for BK, -c 0 for BE, -c 40 for VI, -c 48 for VO.

When test fails (in my opinion): in one terminal: nuttcp -il -v -u -c 40 -T 60 -p 5002 in second terminal: nuttcp -il -v -u -c 48 -T 60 -p 5003 For both of them the available band had been divided by half but I expected the video will be very limited.

Do you know what might cause the problems? Thanks in advance.

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