Last week was eComm, the Emerging Communications conference in San Francisco, which I attended for the first time. Actually this is only the second year that the conference has run. There was much to see in the 90 sessions over 3 days, so I'm still digesting the ideas, but one thing that struck me as interesting was a talk on OpenBTS, i.e. a GSM wireless network released as open source.
OpenBTS offers a wireless interface that is functionally equivalent to a regular 900MHz GSM network, in that in can route calls and texts between phones on the same network. In the back-end it gets even more interesting though, with the ability to convert GSM calls to SIP, and so interconnect OpenBTS with IP networks and the general PSTN. Turning their back on conventional SS7, most of the separate functional blocks of a GSM network disappear (BSC, MSC, VLR, HLR etc), to be replaced by a single Asterisk backend, which treats the mobile phones as extensions on a PBX.
The target for OpenBTS is to be able to create a cost-effective wireless network where none exist today, for example remote locations like oil-rigs, or where the commercial world has turned its back on poorer countries. It is also possible that it might be used in disaster zones (think of Hurricane Katrina) where incumbent networks have been disabled.
Since it uses licensed specturm, it is unlikely we'll see this being used commercially in the West, and I can't help but think that they will have intellectual property problems since there are a large number of GSM patents. However, I wish them luck, and see it as a bold and innovative move.
An interview between Lee Dryburgh (eComm founder) and David Burgess (creator of OpenBTS) can be found on the eComm blog.