Phihong Proposal for High-Power PoE Accepted By IEEE Committee

April 02, 2007 by Jeff Shepard

Phihong USA announced that it had made a proposal to the most recent meeting of the IEEE802.3at task force to allow midspans used in Power-over-Ethernet (PoE) applications to put the power onto the data pair as required for Gigabit systems.

"Numerous presentations to the IEEE have proven that this can be done without affecting the ‘channel characteristics’ as specified in IEEE802.3 specifications," said Keith Hopwood, Vice President of Marketing for Phihong USA.

Putting the power on the data pair is required for Gigabit systems as all wires are used to carry data. If 4-pair powering gets ratified then it will also be required to carry power on all the wires that carry data as well. Phihong claims that its PoE midspans already do this. Many customers have already implemented this although it is technically outside the current IEEE802.3 specification. This approved resolution puts specific text into the new specification that makes it official.

The new standard is now in draft, and many items can still change. The standard is still a year away from ratification, but it is now possible to build hardware that meets these requirements with a high degree of confidence that they will be compliant to the standard. When implemented as a standard, IEEE 802.3at (PoEPlus) will not only allow POE in Gigabit systems but will enable at least 30W of power and potentially up to 60W. Phihong has already developed many products that deliver high-power PoE, but most customers would prefer a common industry standard for all devices on the market.

Applications that will benefit from the increased IEEE802.3at classifications and voltage include wireless multi-radio access points, Pan Tilt Zoom security cameras, IP phones with streaming video displays, computer workstations and LCD display panels. Other emerging applications, including emergency lighting, security system sensors and even medical monitoring, will greatly benefit from combining data and centralized backup power.