WMM QOS

[Ahmed Abd El-Moaaz]

i really donot know if QBSS and TSPEC can be used together at the same time in the WLAN (access point send the beacon with the QBSS then the client use the TSPEC) or i just choose only one option (QBSS or TSPEC) in the WLAN

does TSPEC and QBSS work with all 802.11/b/g/a or each works in specific band

ip phone 7921g when it works in 802.11b/g does it use QBSS and TSPEC or only one QBSS or what

[migilles]

Yes can have QBSS enabled as well as TSPEC (CAC).

In the latest 792x loads, QBSS is used only for display purposes (to display the channel utilization values).

QBSS will be enabled if you have WMM or AP CAC enabled.  Not recommended to enable Client CAC as that QBSS version advertised by the AP is not CCA based (does not account for all energy on the channel).

So for CAC with the 792x, we use TSPEC, which will provide inbound and outbound CAC when enabled.

[Ahmed Abd El-Moaaz]

thx SAR for ur reply but i have another question does TSPEC work on 802.11b/g/a or just on 802.11a

and QBSS works only in 802.11b/g but doesnot work with 802.11a ????

[migilles]

Yes the Cisco AP supports QBSS and TSPEC on both 2.4 and 5 GHz radios.

[Ahmed Abd El-Moaaz]

this is from student guide

You can enable WMM, thus sending the 802.11e standard QBSS Load IEs for nonproprietary

Cisco phones and check the AP CAC limit box to replace it with the Cisco IE for the Wireless

IP Phone 7920 and 7921G phones. The various QBSS IEs use the same ID, and, therefore, the

three QBSSs are mutually exclusive. For example, the beacons and probe responses can contain

only one QBSS IE. Also, QBSS is not supported when using 802.11a.

as u can see QBSS is not supported on 802.11a so i think something is missing here

[migilles · Accepted solution]

That document is either incorrect or outdated. 

Probably outdated since it still mentions the 7920 which we have not sold for over 3 years now. 

QBSS and TSPEC are definitely supported on 5 GHz (802.11a).

Try it and see for yourself first hand.

See the 7925G Deployment Guide for more info.

http://www.cisco.com/en/US/docs/voice_ip_comm/cuipph/7925g/7_0/english/deployment/guide/7925dply.pdf