It is known variously as B.P.L, for broadband over power lines, or as HomePlug. As a concept, it has been around for a long time. What is new in the last two years is a series of technical breakthroughs, mainly in chips designed by Intellon, a tiny company in Ocala, Fla. These chips have made power-line transmission fast enough, cheap enough and reliable enough to merit serious attention. A standards-setting group called the HomePlug alliance has also played an important role.
The idea behind this approach is that plain old electric wires can do double duty in carrying high-speed digital data, much the same way that cable, fiber-optic and D.S.L. networks do. The advantage is that the needed electric wires are already there, bringing power to nearly every house in the nation and almost every room in each house. So for a tiny fraction of the cost of building new connections, this approach could help solve the familiar "last mile" problem: how to bring Internet service from trunk lines to each school and household. It can immediately deal with the increasingly vexing "last hundred feet" problem: how to bring broadband service to every nook and cranny of a building.
Bill Berkman, the chairman of Current, said the power-line system had advantages for utilities like Cinergy because it made their electric grids "intelligent." The systems can automatically sense service interruptions, problems and performance levels more quickly and precisely than they otherwise could. But no one, including Mr. Berkman, contends that power-line transmission is the exclusive or final answer to broadband problems.
"It's another tool in the toolbox," he said, to be used with cable, D.S.L., a promising wireless technology called WiMax and other systems, employing each one where it is most efficient. John H. F. Miner, the president of Intel Capital, said that in the long run, all of today's data networks might have to give way to fiber-optic systems with even higher capacity. But that could take a long time - and in the short term, power-line transmission could be valuable not only in the United States, but also "in places with inferior telecom infrastructure but great power grids, like Russia."
Monday, 12 July 2004
