This section provides instructions for managing 802.11n access points on your network. The 802.11n devices support the 2.4 and 5-GHz bands and offer high throughput data rates.
The 802.11n high throughput rates are available on all the 802.11n access points for the WLANs using WMM with no Layer 2 encryption or with WPA2/AES encryption enabled.
The 802.11n-only access points can filter out clients without high-throughput information element on the association request. The 802.11n-only access points access points reject association requests from clients without high-throughput information element (11n).
In the 802.11n high-throughput mode, there are no 802.11a/b/g stations using the same channel. The 802.11a/b/g devices cannot communicate with the 802.11n high-throughput mode access point, where as the 802.11n-only mode access point uses 802.11a/g rates for beacons or management frames.
Some Cisco 802.11n APs may intermittently emit incorrect beacon frames, which can trigger false wIPS alarms. We recommend that you ignore these alarms. The issue is observed in the following Cisco 802.11n APs: 1140, 1250, 2600, 3500, and 3600.