POE standard's stronger sibling emerges

The popularity of power over Ethernet, a viable method of powering wireless LAN access points and user devices, seems to be gaining momentum with the imminent development of a new, more powerful standard. The IEEE has created a new task force to study the new POEPlus, or 802.3at standard. The new standard will provide increased power of up to at least 30 watts at customer premises equipment, an increase from the existing POE standard's (802.3af) 13 W.

POE allows the deployment of premises-based switching equipment without external power sources. Proponents say the solution minimizes network wires, resulting in easier maintenance and greater flexibility of installation. The POEPlus standard is intended to provide higher wattage for devices such as wireless LAN access points, VoIP phones, network security cameras and laptop computers.

Igal Rotem, CEO of POE equipment-maker PowerDsine, said his company led the initial study group and is active in the newly formed task force.

“We are expanding the market quite dramatically, enabling many more applications to utilize POE,” he said.

After getting a general consensus on the need for the higher standard, a study group was formed to research the applications, cost and opportunities of POEPlus. The group submitted its findings to the IEEE forum in July. The POEPlus task force was then formed and is the next step in the formal ratification of the new standard.

Rotem said the new task force's study of POEPlus will probably take about 18 to 24 months, and several vendors are involved, including Alcatel, Avaya, Cisco Systems, Fujitsu, Hitachi, Hewlett Packard, LG, NEC, Nortel Networks, 3Com, Samsung, Siemens and Toshiba.

“They all are part of the standards group and they are closely participating and contributing to the technology effort,” he said. “Some are active customers, some will be active customers and that's more the landscape.”

Rotem said the penetration rate for POE in general is still relatively low, below 20%, because the 802.3af standard has only been ratified since 2003. He believes the technology will steadily gain favor after POEPlus is ratified.

“POEPlus is going to create a de facto new way to power devices. With POE there was a big change because you moved from main powering to POE powering, the major difference is that category 5 cable in the RG45 and the LAN outlet are the same exact outlet all over the world, he said.

“For the first time, what is now happening is you've created a real universal power connector, something that you can connect to your device and you know that wherever you go it will be exactly the same type of connection.”

802.3at Objectives:

• 802.3at should operate on CAT5 and higher infrastructure, unlike 802.3af, that had take into account the CAT3 limitations

• POEPlus should follow the power safety rules and limitations pertinent to 802.3af

• POEPlus power source equipment (PSE) must be backwards compatible with 802.3af, being able to power both 802.3af and POE Plus PDs

• POEPlus should provide the maximum power to PDs as allowed within practical limits, at least 30 W

• 802.3at PDs, when connected to a legacy 802.3af PSE, will provide the user an indication that a 802.3at PSE is required.

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Source: IEEE