WLC QOS Profiles

[rchester]

In the profiles under Wired QOS Protocol, what 802.1p value is the frame marked if the protocol is none (untagged?)

[Jacob Fussell]

The controller actually isn't doing any marking up or down itself. It relies on the markings coming in from the wired world to do translations. That 802.1p setting is actually making sure at the radio itself that the wireless frame can't get a value any higher than the 802.1p value set in the controller. So if the value is zero at the controller then the wireless frame must use the best effort queue in the radio itself. The best document to depict this is the 4.1 mobility design guide chapter on qos.

Sent from Cisco Technical Support iPhone App

[rchester]

I understood QOS profiles were there to cap the 802.1p

(controller) and DSCP (Access point) value to stop a device from gaining an advanatage on a particular WLAN?

Also the values are variable in the QOS profile so shouldn't they actualy be changing something?

Thanks

[Jacob Fussell]

The 802.1p value you configure in the controller is only assuring that the actual 802.11 wireless frame can't use a higher EDCA queue in the radio itself, than what is configured at the controller.  Let's say for example that for your Platinum QoS profile in the WLC, you configure 802.1p = 4.  If you then send voice traffic on a WLAN using Platinum QoS, the wired DSCP should be EF....so when this voice packet gets to the radio itself, instead of using the Voice AC, it will be demoted to the Video AC due to the 802.1p=4 value you set in the WLC.  Conversely, if you have your Platinum 802.1p=6 and send voice traffic with DSCP as best effort then when the packet gets to the radio itself it will also use the Best Effort AC in the radio and not the Voice AC.

[rchester]

Thanks Jafusel,

I have also watched the "FastLane" video on Cisco WLC QOS and this is very good at clearing things up. Although Fastlane doesn't aggree  with the  Cisco Enterprise mobility document regarding handling of packets when the QOS profile configurationhas no wired protocol set.

Cisco say same as profile heading (eg Silver or platnum etc) but Fastlane say no marking and will be put in the standard dcf queue for transmission at the AP.