Cable calls on IP voice: Comcast claims positive trial results

Following in the footsteps of integrated communications providers, cable providers have taken the first step toward offering IP telephone service over their existing hybrid fiber/coax networks. Comcast last week announced a small trial of IP telephony over its is network, and officials said other cable companies also are in the testing phase.

Comcast is one of only three or four cable companies that currently have trials under way, said Dick Day, general manager for Motorola's cable unit, confirming that voice over IP is the wave of the future for cable modems.

"It's pretty broadly spread, and there's been lots of industry reports on all the capabilities various companies are bringing to this area," he said. Day wasn't at liberty to identify other testing companies.

Comcast, the first to publicly announce it intentions, is conducting a 25-person technical trial in Union, N.J., based on Lucent Technologies' CableConnect Solutions, including Lucent PathStar access servers. Comcast also is using Motorola's Cable Router cable modem termination system in the headend and Motorola's multimedia terminal adapter in subscribers' homes.

Users can call other trial subscribers and call "off network" worldwide through a link between the access server and the public network. Features include operator assistance, 411, call waiting, caller ID and call forwarding. Lucent's IP solution enables Comcast to offer the voice service over the same network on which it offers data and video.

The trial, which began in September, is an attempt to track quality of service, the network's capability to interoperate with the public network and provisioning and billing, among other things, said Dee Dee Nye, vice president of cable communications for Lucent. Despite some skepticism from the industry, the trial has proved that full deployment is closer than most think, Nye said.

"The next step beyond this is commercialization," which could come as soon as the second half of next year, she said. If so, Comcast could be one of the first multiple systems operators to implement CableLabs' PacketCable 1.0 specifications for transmitting multi-featured IP phone calls over HFC.

That's optimistic, says Patti Reali, an analyst for Dataquest. She believes 2001 or beyond is more realistic.

"You've got to get standards," she said, explaining that the more data-centric data over cable service interface specifications (DOCSIS) 1.1 standard has not yet been tested in the market. Beyond that is the initiative merging the cable modem certification process, which will bring more standards and new technologies, she said. "You have a while."

But Nye argues that the cable industry's commitment to standards actually is pushing commercialization along. DOCSIS 1.0 is available and tested; Packet Cable's first-round specification and testing has started and "we know what 1.1 is going to look like," she said. Combined with the fact that Comcast is using the PathStar access server, a proven platform with general availability in the competitive local exchange carrier marketplace, the company is speeding toward commercial deployment, Nye said.

That's progress, but it doesn't mean that IP over HFC is ready for prime time. "You still have huge, huge technological issues," Reali said, pointing to yet-to-be-made decisions on powering the network, network demarcation points, network termination and outside plant environment.

While Comcast officials were unavailable for comment last week, Nye acknowledged that "telephony over IP is very difficult," and several players have had a hard time getting features working. The Comcast trial, however, has "really proved that IP telephony is ready for prime time," she said.

Cable providers stand to reap the benefits. "It gives you a flexible platform so you can combine voice, video and data," Nye said. Financial comparisons on equipment alone for two networks vs. one show a 40% to 50% savings, she said.

As for customers, "This is going to be a very inexpensive way to add telephone service in their homes," Day said.

With or without voice attached, cable modems have found a place in the industry. Motorola, for instance, is expected to announce this week that it has now shipped 1 million cable modems.