CableLabs has selected advanced voice codecs from Broadcom Corp. and Global IP Sound for all future PacketCable 1.1- and 1.0-certified and qualified embedded multimedia terminal adapters (eMTAs) and PSTN media gateways.

Both vendors have agreed to make their selected codecs available on a royalty-free basis. CableLabs issued a request for proposal on the subject back in May 2002. The selection becomes formal in April 2005, pending successful interoperability demonstrations. PacketCable today mandates G.711, a barebones 64 kbps codec used by the public switched telephone network (PSTN).

Global IP Sound President and CEO Gary Hermansen said the selection of voice codecs should boost vendor adoption of the PacketCable spec.

It will also free vendors from the fees they traditionally pay to use standard codecs, said John Gleiter, director of business development for Broadcom's communications group. Using royalty-free codecs, he added, will be of tremendous benefit to media gateway makers, whose codec fees are usually amplified because they must pay based on the number of lines supported. They also support multiple codecs, in many cases.

Among the selections, CableLabs picked Broadcom's BroadVoice16 codec and Global IP Sound's iLBC product.

BroadVoice16, which runs at about 16 kbps, is designed for toll-quality VoIP networks. Broadcom claimed the technology can reduce the bandwidth requirements of VoIP services by more than 50 percent.

Global IP Sound is supplying a version of its iLBC product that operates at 15.2 kbps, and delivers "speech quality equal to or better than G.729 and G.723.1," according to a company product description.

Hermansen said the next step is to get the company's codec implemented with eMTA and media gateway manufacturers.

Still, the PacketCable voice codec project is not a slam-dunk when it comes to intellectual property (IP) issues, argued Dennis Rauschmayer, director of marketing for cable modem products at Texas Instruments.

Although TI plans to support both codecs, he said there's a concern that the intellectual property shareholders behind Broadcom's codec are not entirely clear.

"Is someone going to pop up next year or the year after asking for money after units are deployed?," Rauschmayer asked. "We're not entirely comfortable that [BV16] is a completely royalty-free codec."

But why isn't that same concern applied to Global IP Sound?

Because Global IP Sound's technology "has been much more public" and has been run by the Internet Task Force, Rauschmayer claimed.

Broadcom said TI's concerns are unfounded, noting that the company hired a group of Ph.D.s with a combined 40 years of experience in the area to research the subject when Broadcom kicked off the BroadVoice project four years ago.

"We wholly own the IP on BroadVoice," said Broadcom's Gleiter. "One of the objectives was that it had to be a Broadcom-originated project. We are very confident that we are IPR (intellectual property rights) clean. They [TI] are just trying to poke holes."