802.11r - R is for Rapid
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.
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