802.11r - R is for RapidBy CWNP On 08/26/2008 - 8 Comments
Soap Box: On
802.11r ratification is the most important standard to hit the Wi-Fi industry in a long time - yes, even more important than 802.11n. 802.11i was sorely lacking - giving us only fast roam-back (to an AP to which your client was previously associated) and preauthentication, which is slow and rarely supported by WLAN infrastructure providers. In the absence of a standard, many WLAN infrastructure vendors (Motorola, Colubris, Aruba, Cisco, Meru, etc.) have been using Opportunistic Key Caching (OKC) - also called Opportunistic PMK Caching. Both the client device and the WLAN infrastructure have to support this for it to work, and on laptop computers, that gives us only Microsoft's WZC client and Juniper's Odyssey client. While both are popular, they don't represent the entire industry - not even half when you consider how many appliances like VoWiFi phones there are in the market.
Now that 802.11r is upon us, I predict (read: guarantee) that all WLAN infrastructure providers will adopt it into their WLAN infrastructure code as fast as they possibly can. Further, we will see client software support for 802.11r protocols little-by-little over the next 12 months until pretty much all client software and appliances (Wi-Fi badges, handsets, handhelds, scanners, etc.) all support it. As an industry, how can we not? Fast, secure roaming - called Fast BSS Transition (FT) by the 802.11r amendment - is a must to asure applications don't break while on the move. And since mobile applications have reached critical mass over the last 6 months, getting 802.11r protocol support into everything Wi-Fi related should be priority #1 for vendors.
Soap Box: Off
802.11r, and it's sister, 802.11k were ratified on July 15th and June 12th respectively. Where the heck is my 802.11r support already? It's not like vendors didn't know it was coming...they were helping build the standard.
Now then, if you're thinking, "where can I learn about FT stuff?" I have just the answer for you. I've written a very abbreviated whitepaper on this topic, covering the humble begginings of 802.11 roaming and progressing through 802.11i AKM, proprietary options, and then 802.11r AKM. Here's the link:
(It's free to sign up and to get the whitepaper)
If you can make it to the end of the whitepaper without a migraine, you probably enjoy Wi-Fi technology a little too much. ;) I hope this helps. Please feel free to post how 802.11r ratification will affect you and your company.