QoS Configuration for NME-AIR-WLC

[Dave Lewis]

Hello,

I have a question on the correct QoS configuration for a VoIP deployment. I have followed the steps referenced here but have two questions..

1) The last recommendation in the list is to set DCA channel sensitivity to High to avoid changes during business hours. I think this should be Low? The manual states "Low—The DCA algorithm is not particularly sensitive to environmental changes."

2) The recommendation is to trust dscp on AP uplinks and to trust cos on the WLC uplink. However I can't find any configuration guidelines for configuring QoS if the WLC in question is an NME hosted in a 2921.

2a) The link between the switch and the 2921 is an 802.1q trunk so should I trust cos on this link rather than dscp?

2b) What configuration should be on the 2921? Create a policy-map and apply it to the uplink port?

2c) Should there be a service policy assigned to the In1/0 interface for the WLC itself?

Any thoughts appreciated.

Thanks,

Dave

[Dave Lewis]

Well I appear to have answered question 2 after I stopped being lazy and did some packet captures.

No configuration required on 2921 as packets captured from In1/0 and Gi0/0 show correct DSCP markings on RTP and SCCP packets.

Would still be interested to know on question 1 though.