IEEE starts revving up Power over Ethernet (PoE) standard

WITH INTEREST growing to use the installed base of electrical power lines for Internet and other broadband communications, the Institute of Electrical and Electronics Engineers (IEEE) has started working on a standard to define the nature of the communication channel that Power over Ethernet (PoE) will use, an essential step to help manufacturers develop devices needed to commercialize this approach.

The standard, IEEE P1901, "Standard for Broadband over Power Line Networks: Medium Access Control and Physical Layer Specifications," should make it easier for high-speed communication equipment to be used with AC power lines. An entity-based standard, participants developing P1901 include companies and other organizations from the power, utilities and broadband communities. It is targeted for completion in early 2007.

IEEE P1901 will apply to broadband-over-power-line (BPL) devices for first-mile/last-mile connection to broadband services, as well as those for the local area networks and other data distribution systems to function over copper power lines in a building. The standard will create a balanced and efficient BPL channel that has the bandwidth and quality of service needed by all users.

"The ability to transmit digital data over power lines from substations to homes and offices is attracting attention because it transforms wall outlets into Internet portals," says Jim Mollenkopf, co-chair of IEEE’s BPL PHY/MAC Working Group. "This resolves the tough task of linking long-distance fiberoptic cables to individual computers, and should make the Internet even more universal than it now is.” Mollenkopf thinks that if BPL is to become widespread, there must be a robust standard that supports the use many types of BPL devices. “Our intent is for IEEE P1901 to be that standard," he adds.

Jean-Philippe Faure, the working group’s other co-chair, says BPL communications means an open media, shared by many devices. "The physical and medium access layers to be defined in the new standard will ensure that BPL devices operating on the same network will be able to coexist without conflict,” says Faure. “It also will allow for interoperability among BPL devices from different vendors so end users can create viable systems according to their needs."

In access BPL systems, communication signals are imposed on electrical distribution feeders and travel medium-voltage lines to a step-down transformer at a residence or business. A repeater/router moves the signal to the low-voltage wiring where it can be accessed through a modem plugged into any outlet. BPL also allows utilities to deploy devices that can make electric service more efficient and reliable by monitoring system problems and performance.