* IEEE forms Power over Ethernet Plus study group
The IEEE recently established a study group to look into increasing the power available through the Power over Ethernet standard.
The standard, approved back in mid-2003, provides for Ethernet signals and electrical power to travel over the same twisted-pair cables. But there is a limit to how much power can be sent – and that limit is 12.95 watts.
Despite that limitation, there are plenty of uses, and the standard seems to be ever more widely implemented to support IP phones, wireless access points and so forth.
But with higher power support, other applications become possible – so the Power over Ethernet Plus study group was formed. According to presentations on the group’s site, these applications include video phones, biometric access controls, RFID readers, higher-speed wireless access points, point-of-sale devices, and even thin clients.
Video phones sound pretty cool to me. But they typically require about 25 watts of power, according to the group’s site. Surveillance cameras can be supported with current PoE technology, but if you want to be able to pan, zoom and tilt the camera you are looking at more than 20 watts. Current wireless LAN access points can be supported with PoE, but for IEEE 802.11n and its promised 100M bit/sec of wireless bandwidth, the needed power is also in the range of 20 watts.
According to the study group’s site, power over Ethernet could be increased to 30 watts or more. There are lots of issues to consider to make that happen, however, and that’s why the group at this point is only getting started.
