Cisco 9971 Deployment Manual page 51

Individual access points can be configured to override the global setting to use dynamic channel and transmit power assignment
for either 5 or 2.4 GHz depending on which band is to be utilized.
Other access points enabled can be enabled for Auto RF and workaround the access points that are statically configured.
This may be necessary if there is an intermittent interferer present in an area.
Enable ClientLink if using 802.11n capable access points.
CleanAir should be enabled if using capable access points (i.e. Cisco Aironet 3500 Series).
Cisco Unified IP Phone 9971 Wireless LAN Deployment Guide 51