The IEEE has completed 802.11r, a standard that lets Wi-Fi devices roam quickly between access points, improving the performance of VoIP on enterprise LANs.

The IEEE 802.11 standards were originally defined with single access points in mind, but in offices multiple access points are needed. Devices can move from one access point to another, but it takes around 100ms to re-associate, and several seconds to re-establish authenticated connections using 802.1x.

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