This is great news for wifi networks which, until now, would drop connections when guests moved from AP to AP. This is especially good for those who use wifi VOIP handsets, since it promises to provide a seamless handoff from AP to AP just like the cellular phone network does!
Called 802.11r, or “Fast Basic Service Set Transition” (catchy, huh?), it is the result of four years of research and testing. The IEEE feels that it’s ready for the public, and they approved the standard July 15th.
My educated guess is that this standard could be added to many existing wifi routers, APs and client adapters via software update. Let’s all let Fon know that we need this added to the OpenWRT/Fon hotspot firmware! It would be wonderful to be able to stroll around in zones where Fon and/or their partner networks have lots of hotspots, and enjoy unbroken wifi connections, voice calls and instant messages.
How does it work? I don’t know yet. However, it would seem likely that there must be a background infrastructure where a client’s connection is proxied upstream, and so wifi APs downstream are slaved to a central controller. This isn’t too new of an idea, but ratifying a standard is an important, big step in making this widely compatible. Hopefully, it can serve legacy wifi clients at the same time, and is also compatible with wifi encryption.
This brings Fon’s original dream back into range; Fon was originally concieved of as a FonSpot/JoikuSpot type software application running on PCs, and later, as a hardware router running customized firmware (Linksys), which provided wifi for VOIP handsets. This would function much like today’s femtocells, only it would challenge the telco monopolies by providing cheap calls over wifi. Wifi for other devices was merely a potential side benefeit, and there was no emphasis on “revolutions”, “communities” or selling day passes.
A combination of 802.11r plus a transparent SIP proxy would permit many people to share the same wifi connection for VOIP calls. Currently, SIP would not work at a Fon hotspot for incoming calls, without port forwarding. The consequence of that would likely be to block anyone else from using SIP at the same hotspot.