US : Not that long ago, many market-watchers thought that Unlicensed Mobile Access (UMA) had run its course as a means of bridging cellular and Wi-Fi networks. However, because of the delays in the growth and development of viable competing solutions (SIP, or VCC), the opposite is true: UMA services, devices, and subscribers are still growing, and subscriber numbers should reach 65 million by 2012.

A new Research Brief from ABI Research indicates that at least seven handset vendors currently offer UMA-enabled handsets, and mobile operators are actively pursuing the technology.

“Until recently, proponents of competing fixed-mobile convergence solutions frequently cited the fact that UMA was only usable with 2G or enhanced 2G cellular services,” says principal analyst Philip Solis. “But recently, the UMA client software has received an upgrade that will allow it to work with 3G handsets and services, offering another mobile broadband FMC option that will be viable for some time to come.”

A number of major telecom operators around the world have been busy with UMA: they like the idea because it relieves 3G network congestion. British Telecom now has over 40,000 customers for its consumer UMA-based service, Fusion, and has launched a corporate version in eight European countries.

France Telecom countered with a similar service called Unique, selling over 250,000 UMA handsets, and T-Mobile launched a large-scale UMA-based service in the US last month. Several other carriers worldwide are also testing the UMA waters.

The ABI Research Brief, “Unlicensed Mobile Access (UMA): Vendor Ecosystem, Operator Deployment Activity, and Subscriber Forecasts” considers the major vendors in the UMA ecosystem and tracks the way UMA is working its way into new products, including cellular femtocells. It forms part of three of the firm’s subscription Research Services: Mobile Broadband , Fixed-Mobile Convergence and Wi-Fi.