Just last week I updated my Cisco 2504 to the latest software version, 18.104.22.168.
One of the updates that stuck out to me was under the security configuration of a wireless LAN, Fast Transition.
What is Fast Transition
Fast Transition is Cisco’s lingo for IEEE 802.11r. 802.11r is an amendment to IEEE 802.11 and was ratified in 2008. The standard defines fast roaming between APs.
How Does it Work
The concept of fast roaming is that the device creates a handshake with another AP even before the client roams to the new AP. This allows the client to roam to another AP without re-authenticating.
Caveats and Restrictions
A wireless client not compatible with 802.11r will not be able to join a WLAN with Fast Transition (802.11r) enabled. You will have to create another WLAN with a different SSID that has Fast Transition disabled.
Fast Transition will only work with open and WPA2.
Fast Transition is not supported with:
- APs in standalone mode
- EAP LEAP method
- Legacy clients without an 802.11r enabled driver
Configuring 802.11r on a Cisco Wireless LAN Controller
First off, Fast Transition will not be shown on your controller unless you have at least version 22.214.171.124 on you WLC.