The newest Wi-Fi protocol, 802.11r, which has become the de facto "Wireless VoIP standard", is now a published standard of the Institute of Electrical and Electronics Engineers (IEEE) standards board.
802.11r has been in the works since 2004, with the express purpose of developing a Wi-Fi connection that can quickly pass between access points. A go-ahead for publishing the final draft of the standard was given by the 802.11r task group last January.
Devices supporting 802.11r will be able to hand over connections in approximately 50 ms, just under half the time it takes to swap connections on other standards -- to say nothing of the time it takes to authenticate the connection securely.
Enterprises with wireless VoIP networks have had to improvise solutions because of this difficulty in re-connection, with varying results. In general, however, "VoIP Roaming" has been a concept lying in wait.
As we have seen with municipal Wi-Fi, deployments of 802.11 wireless routers are costly and work best on a smaller scale. It is therefore unlikely that 802.11r will ever be turned into a widespread VoIP network outside of the enterprise setting.
The Wi-Fi standard that enables more throughput for general-purpose devices, 802.11n, was proposed not long after 802.11r. Though it has been approved conceptually, a final draft of that standard still awaits publication by the IEEE's 11n task group (TGn). Version 5 of the draft was approved by a 90% majority of IEEE voting members just last month; but there's a version 6 on the horizon, and now the final publication of 11n may not come sooner than November 2009. In the meantime, many devices supporting 802.11n have already reached wide commercial distribution.
