Putting the Wire Back Into Networking

Back in the Stone Age of home networking, anyone who wanted to play on a computer not hooked directly into an Internet connection had to snake phone lines or Ethernet wires across floors and up staircases.

People talked about a promising idea: using the electrical wiring already in the house to move data from room to room. One early application, the X10 system for controlling lights and appliances, didn't always work well. The technology was certainly not ready to be used to bring Web pages to computers anywhere in the house.

Along came the wireless network. For , you could get the Internet sprayed across the house and never be tethered by a cord to the wall. It was slow in those early days, notoriously unreliable, and open to interception if you couldn't bother with setting up the encryption codes.

But it caught on. According to estimates made by Parks Associates, a market research firm based in Dallas, about 12.5 million homes now have wireless networks; another 10 million homes, mostly newer ones, have Ethernet or coaxial cables in the walls.

Cheap and ubiquitous is a hard combination to beat. But wireless networks did not end the quest to put data through electrical wires.

Technology companies continued to work on the idea. Some tried using phone circuits. A version for power lines called HomePlug came out in 2002, and while it hardly affected sales of wireless network equipment, it sold enough that major companies like Intel, Cisco, Sony, Sharp and Comcast created the HomePlug Alliance to push for next-generation products, with the first to come out later this year.

"I don't think anyone had expected the technology to progress," said Andy Melder, senior vice president for sales, marketing and business development at the Intellon Corporation, a maker of chips for home networking devices that use power lines.

Some companies are not waiting. Panasonic, Netgear and Marantz are already offering products that will move data through home electrical lines faster than routers using the current Wi-Fi standard for wireless networking, 802.11g.

Panasonic started selling its HD-PLC Ethernet adapters for power lines last month. A 0 starter kit provides two units, each about the size of two sticks of butter.

One adapter is attached to a router with a short Ethernet cable and plugged into a nearby wall outlet. The second device is plugged into an outlet elsewhere in the house. When a computer is linked to it with an Ethernet cable, data is transmitted through the home's electrical wiring at speeds of up to 190 megabits a second. Up to seven devices can run on the network.

Netgear, a leading maker of wireless networking gear, will be selling a similar system next month for about 0. (Every additional module costs about 0.) It moves data at a slightly faster rate.

Marantz says its ZR6001SP receiver will send music to special speakers in another room over power lines. The system, which includes both devices, will sell for about ,300. Additional speaker units cost about 0. The music listener controls the receiver and the CD players or iPods connected to it from a control pad on the speakers.

"We were getting many requests from installers, like how do I get multiroom audio if I can't run wires," said Kevin Zarow, vice president for marketing and product development. The Marantz device also solves the problem of running speaker wires across a room.

At first blush, these products may seem to be nonstarters. After all, who would want to pay two or three times the price of a wireless network?

The answer lies in the simplicity.

Robert Stephens, founder and "chief inspector" of the Geek Squad installation and troubleshooting division at Best Buy, said installing wireless networks was the leading reason for house calls. "It's why most people need us," he said, noting that the complexity of installing a wireless network is evident from the fact that return rates on wireless networking devices drop to nearly zero when his installers do the work.

The Panasonic network over power lines, on the other hand, was up and running in less than five minutes. Encryption was automatically enabled, and there was no need to configure anything. It worked well even in a house with 90-year-old cloth-wrapped tube-and-knob wiring where the lights sometimes flicker. And though Panasonic warns that operating a power drill or a vacuum cleaner on the same outlet may cause an interruption of Internet service, running both while using the HD-PLC on the old wiring did not pose a problem.

The makers of all three products said that people who cannot get whole-house coverage with a wireless system or those plagued by dead zones might find it appealing.