Santa Clara Calif. -- Opposing camps in powerline home networking will face off at an IEEE meeting in Boston this week over the path toward a unified standard. It's unclear whether anything will come of the eleventh-hour calls for compromise in advance of the Boston event, but separately players are stretching their technology to compete with everything from 802.11 to ZigBee.

Companies as diverse as Cisco, Echostar, Philips and Intel expressed support for powerline at the annual HomePlug Alliance convention here last week. But they also called on all sides to embrace standards and lower costs in a highly competitive environment.

Indeed, the Multimedia over Coax Alliance (MoCA), a rising star among cable TV service providers, will turn up the heat this week, when it announces a 1.1 version of its spec that delivers 175 Mbits/second at the media access control level and supports parameterized quality-of-service.

By contrast, the two leading powerline technologies claim data rates of 95 and 65 Mbits/s and lack the parameterized QoS some service providers require.

On a brighter note, the HomePlug group has ratified a spec for a 700-kbit/s control network that will challenge ZigBee for networking of lights, alarms and white goods. The competing Universal Powerline Association (UPA) is working on a similar spec, which could be announced before mid-2008.

Meanwhile, executives from HomePlug, the UPA and the Consumer Electronics Powerline Communication Alli- ance (CEPCA), a group of mainly Japanese conglomerates, were in discussions last week on whether they could hammer out a joint proposal in time for this week's Boston meeting of the IEEE 1901 committee, which aims to set an overarching global standard for powerline home nets.

The IEEE 1901 group is considering two competing proposals. One brings together separate technologies from HomePlug and Pana- sonic; the other is from the UPA and has some backing from CEPCA.

HomePlug backers say they could have enough members to force and win a vote on their proposal in Boston. The effort defines a protocol that ensures separate HomePlug and Panasonic networks will not interfere and will be able to share data, as long as vendors support both entities' separate physical-layer technologies.

Not surprisingly, Oleg Logvinov, chief strategy officer of HomePlug and chief executive of Arkados Inc., which makes HomePlug chips, expects to see the Boston meeting select the HomePlug proposal. HomePlug now has 75 members, including Cisco, Comcast, Intel, Motorola, Sharp and Texas Instruments.

"That [outcome] would be bad for everyone," countered Chano Gomez, vice president of technology for Design of Systems on Silicon S.A. (DS2; Valencia, Spain), currently the sole chip maker for the UPA approach.

A pitch for unified PHY

UPA members say the better solution would be to define one physical-layer technology on which all parties could agree--even if doing so would require all sides to revise their silicon. Both HomePlug and UPA members said they would be willing to rework their chips, but it's not clear the camps can reach consensus on a single proposal.

"Right now, e-mails are flying back and forth between senior people in each organization to try to move this process forward," Brian Donnelly, chairman of the UPA marketing group, said in an interview last week. "We want to have an agreement before going into the [Boston] meeting."

Donnelly is also vice president of marketing and business development at Corinex Communications Corp., which sells powerline systems based on chips from DS2. "If we have to force our primary silicon provider to make concessions, we will do that, and we have buy-in from DS2," he said.

"We need a standard going forward," said Martin Manniche, senior director of engineering at Linksys, a unit of Cisco Systems that makes Wi-Fi and powerline networking gear.

At the HomePlug event, Manniche called on chip makers to design more-integrated parts, in order to drive down costs of powerline modules to $50 per pair. He also called on the industry to adopt extensions defined by Cisco to the Universal Plug and Play Forum's QoS standards. Cisco's so-called Video Quality Experience spec lets systems restrict access to a network to ensure uninterrupted video delivery.

A separate UPnP effort for similar QoS capabilities "will mostly likely take another 12 to 18 months" to complete, Manniche said, "and the industry can't wait."

Whatever happens in Boston, the HomePlug approach commands a majority of the powerline market and is expected to continue to do so, said Joyce Putscher, principal analyst for home networking at market watcher In-Stat (Scottsdale, Ariz.).

"Having a standard is not always 100 percent critical, because you can also have a de facto standard," she said.

Donnelly said Corinex is selling systems using the UPA approach to more than 30 service providers and 40 utilities worldwide. It switched from HomePlug to DS2 silicon in 2005 because DS2 was the first to deliver chips that offered 95-Mbit/s throughput--data rates the HomePlug group is only beginning to approach this year.