Power over Ethernet

The Institute of Electrical and Electronic Engineers (IEEE) has approved the 802.3af-2003 standard, which defines how power is delivered over Ethernet cables.

Power over Ethernet is already widely adopted in the market, particularly in the VoIP, wireless LAN and IP Security market where it saves up to 50% of the overall installation costs by eliminating the need to install separate electrical wiring and power outlets. Its other major advantage, particularly for IP telephony and surveillance camera users, is the ability to offer continuous operation even in the event of a power failure by delivering battery-backed-up uninterrupted power via the local area network (LAN).

Power over Ethernet has been widely deployed in two formats either as endspan devices, i.e. embedded into switches, or as stand-alone midspan hubs, allowing terminal devices to be power-enabled without upgrading the existing switches.

The new standard covers both categories of Power over Ethernet technology.

‘The standard ratification will add extra impetus to the current trend amongst silicon vendors to design chipsets for laptops and portables that require low power consumption below the 12.95W prescribed in the Power over Ethernet standard,’ said Amir Lehr, vice president, business development and strategic planning at PowerDsine, a vendor who has played a significant role in the creation of the standard.

‘As these devices become less power-hungry and Power over Ethernet becomes the standard in most corporate IT environments, there will no longer be a need for people to carry a variety of different plugs when travelling. Instead the RJ45 jack will become the universal power jack. I confidently predict that in the next five years more than 75% of enterprise network devices will be able to be powered by Ethernet,’ he added.

On June 5, Motorola’s Semiconductor Products Sector and PowerDsine announced that they are to jointly create an application-specific integrated circuit (ASIC) for the Power over Ethernet market.