72Mbit mobile links draw closer

Britain's first Wimax service, with the potential to offer broadband to mobile devices, is launching in Kent in early 2005.

But until standards are in place for mobile use it will be restricted to fixed services to homes and offices.

Wimax conforms to the IEEE 802.16 standard, as opposed to 802.11 alphabet soup used by Wifi, and offers up to 72Mbits/sec per wireless node though this would almost invariably be shared by a number of users.

But the new service being set up by start-up Telabria will not deliver Wimax direct to homes because of the high cost of equipment. Instead it will link up with a network of 802.11 cells, which will cover the so-called 'last mile' to customers.

Telabria founder and chief executive Jim Baker insists, with some asperity, that this is not Wifi because it uses different mechanisms for security and quality of service ð that is, ensuring that uses such as multimedia streaming have the applications they need.

It will use a 5.8GHz band that is part of the spectrum allocated to 802.11a Wifi, but is restricted to approved users. Baker says this means it will not contend with domestic Wifi networks ð and neither will the Wimax link, which operates at 3.5GHz.

Business customers who require higher bandwidths will be able to purchase a direct Wimax connection. Prices of home links will be 'competitive'ð around £20 a month for a link operating at at least 1Mbit.

Intel has been pushing Wimax as an alternative to fixed broadband delivery in cities; but others believe it is more suitable for sparsely populated areas with a poor fixed infrastructure. Kent would not seem to fit into either category, but Baker said broadband provision there is quite patchy.

'DSL has a lot of technical limitations, especially on connection speeds beyond 2Mbits/sec. A lot of communities [in Kent] are outside the range and a lot of those that are within range can't get a faster rate than 512Kbits/sec.'

On the mobile possibilities, he warned: 'You have to have a reality check. We believe this will be used first to backhaul from Wifi hotspots. It is a fixed wireless technology for 2005.'