(Total Telecom Via Thomson Dialog NewsEdge)The number of European telecoms operators deploying voice-over-IP is growing, driven by local loop unbundling and the move towards fixed-mobile convergence, according to VoIP equipment vendor Sonus Networks (News - Alert).

One of the key drivers for alternative network operators in particular is "this whole local loop unbundling phenomenon," Hassan Ahmed, CEO of Sonus Networks, told Total Telecom on Monday.

Sonus has "a number of new customers in the U.K., and in Europe in general," Ahmed said, one of which is a particularly important deal, although the company is unable to name them at this stage. Network construction is already underway though.

A number of altnets in the U.K. have announced their involvement in local loop unbundling, aided by the "very intelligent" regulatory situation, said Ahmed. These players are not going to build on old, circuit-switched technology, he added; broadband infrastructure will be the underlying technology for voice.

"LLU has created a market," said Ahmed.

The majority of the U.K.'s major ISPs have outlined plans for LLU, including Bulldog, Pipex, Wanadoo, Tiscali, Easynet, PlusNet, Carphone Warehouse and AOL.

The same technology will underlie mainstream operators, Ahmed continued. VoIP on the edge will be driven by having a broadband IP last mile to the customer.

"Those operators are typically not early adopters," he noted. They have to build the fibre first, while altnets "do it over DSL".

The move towards fixed mobile convergence is also proving an important driver for VoIP and IP-based services.

"Operators are competing by bundling services," said Ahmed, with IP being the key infrastructure on which to do this.

Triple-play has become quadruple-play, or "the grand slam", with mobile services added to the telephony/broadband Internet and TV bundle.

U.S. cablecos Comcast (News - Alert) and Time Warner have effectively agreed MVNO deals with Sprint (News - Alert) to enable them to add the wireless element, while the recently agreed Virgin Mobile/NTL merger is set to bring a quadruple-play to the U.K.

"It's all about broadband," and being able to deliver converged services over a common infrastructure, including mobile, said Ahmed.