T-Mobile International AG and some of the wireless industry's largest equipment vendors have joined forces to back a new approach for delivering voice services over Long-Term Evolution (LTE) networks, Unstrung has learned.

The new group, which Unstrung understands will formally launch its initiative on March 9, is called the VoLGA Forum. No, not the Russian river -- VoLGA stands for Voice over LTE via Generic Access.

Honest!

The founding members of the Forum are:

• Alcatel-Lucent (NYSE: ALU)
• Ericsson AB (Nasdaq: ERIC)
• Huawei Technologies Co. Ltd.
• Kineto Wireless Inc.
• LG Electronics Inc. (London: LGLD; Korea: 6657.KS)
• Motorola Inc. (NYSE: MOT)
• Nortel Networks Ltd.
• Samsung Corp.
• Starent Networks Corp. (Nasdaq: STAR)
• T-Mobile International AG
• ZTE Corp. (Shenzhen: 000063; Hong Kong: 0763)

LTE, as a packet-based network, will not support traditional circuit-switched telephony. The aim of the new group is to define a set of specifications to deliver circuit-switched voice and messaging services over LTE networks using the generic access network (GAN) standard.

It's a proprietary solution, but the group plans to propose those GAN modifications to the 3rd Generation Partnership Project (3GPP) standards body.

LTE voice battle looms
Operators will face big decisions about how to deliver voice over LTE. Alongside voice over IP (VoIP), the new VoLGA approach could be one of several ways operators will be able to deliver traditional telephony over LTE.

Another solution will be based on IP Multimedia Subsystem (IMS). And yet another could be to tunnel the circuit-switched traffic as a bearer.

Ericsson, for one, backs the new VoLGA initiative as well as IMS-based solutions, but it dismisses the circuit-switched tunnel idea as a "gap filler," and not a long-term solution, says Thomas Norén, Ericsson's director of LTE.

"Both [VoLGA and IMS] can exist, but it would be good for the industry to pick one," he says. "Why do it in two different ways?"

The approach already has some operator support. T-Mobile is one of the founding companies, and T-Mobile (UK) 's technical director Emin Gurdenli told Unstrung in an interview at Mobile World Congress last month that when it decides to launch LTE, "ideally, from day one, we want to introduce voice over LTE." (See MWC 2009: T-Mobile Gets Real on LTE.)

In addition, China Mobile Communications Corp. recently said that its first LTE network will support voice, adding that Kineto's Unlicensed Mobile Access (UMA) -- that is, its GAN -- could be one option for making that happen. (See China Mobile Preps LTE Network.)

— Michelle Donegan, European Editor, Unstrung