WIRELESS: Power line schism erupts

Seattle -- Consumer giant Panasonic and the HomePlug trade group are duking it out in the marketplace and in standards groups in a battle over what power line technology will best suit the digital home.

Panasonic will align aspects of its HD PLC technology with the 802.11 juggernaut in a proposal this fall to the IEEE 1901 group, which aims to set a standard for broadband networking over power lines. Meanwhile, a HomePlug work group is defining a compatible version of that home networking technology for access networks.

"I hope the industry comes together for the sake of users. We need interoperability across the board," said Oleg Logvinov, chief executive of startup Arkados (Piscataway, N.J.), which is shipping HomePlug 1.0 silicon.

So far, competition appears to be the more likely scenario. At the Windows Hardware Engineering Conference (WinHEC) here last week, Panasonic showed retail and OEM versions of its HD PLC technology that hit data rates up to 190 Mbits/second.

Panasonic is now shipping at retail a pair of HD PLC adapters for $200. The company would not disclose the cost for an OEM module version of the product that is sampling now and will hit production in August.

The OEM module is based on Panasonic's MN1A2080L chip, which includes an ARM9 processor, PLC media-access controller (MAC) and physical-layer block as well as a 100-Mbit/s Ethernet MAC. The module uses the traditional Ethernet media-independent interface to link to an external Ethernet PHY.

Panasonic claims the technology enables autoconfigurable security and an OEM programmable notching feature so as not to conflict with amateur-radio operators. Two Taiwanese companies, power supply maker Delta and power line specialist ST&T, are making HD PLC products.

Panasonic is now working to make the proprietary security, quality-of-service and testing regimen of HD PLC compatible with those of 802.11 wireless networks, so that future HD PLC products will be able to use 802.11 authentication servers, routers and other devices. The revised spec will form the basis of Panasonic's proposal to the IEEE 1901 power line group this fall.

"We aim to let people build a single product that can act as an 802.11 access point and a power line connection," said David Hunter, a manager of advanced technology in Panasonic's R&D group, which is based in San Jose, Calif.

The new spec is not expected to make significant changes in the throughput of the HD PLC technology. "There could be some tweaks, but I don't know if it will change things much. A new PHY is still in the labs," said Hunter.

The HomePlug group may respond by proposing its technology to the IEEE, although HomePlug has not made an official decision yet, said Logvinov.

So far only Intellon (Ocala, Fla.) is sampling products based on the 200-Mbit/s HomePlugAV spec. Several chip companies including Arkados, Conexant and others are shipping 14-Mbit/s HomePlug 1.0 products.

Like HD PLC, HomePlug can also be implemented to handle autoconfigurable security or notching to avoid spectrum conflicts, said Logvinov. Because the Panasonic approach is based on a wavelet technology, it could be more limited in distances covered than HomePlug, which is based on fast Fourier transforms, he added.

A HomePlug working group had its first meeting in France last week to hammer out a spec for broadband power line. BPL technology would let power companies use their lines to deliver Internet access based on a MAC and PHY compatible with the home network versions of HomePlug.

"We don't care about access networking at all," said Panasonic's Hunter, adding that compatibility between access and home versions of power line is not a critical feature. "You can mix and match these technologies as long as you have a junction box somewhere," he said.

For its part, Taiwan's ST&T is adopting both the Panasonic and the HomePlug technology with demo products shown at the booths of both groups at WinHEC. An ST&T representative said he believes HD PLC will be big in Japan, but the five-year-old HomePlug effort will also be able to establish itself as a de facto standard.

Both approaches will have similar prices and time-to-market, he added, despite the fact that HomePlugAV is still tweaking its firmware to support video while Panasonic is done with that work. ST&T (Tainan Science Park) started in the early 1990s as a maker of test equipment and now specializes in power line products.