What is PoE?

Power over the ethernet, or POE, is a convenient method of providing power through an Ethernet cable to a remote device such as a VOIP phone or IP camera. It works by injecting power into the data cable and extracting the power at the remote device. POE greatly simplifies the installation of IP devices as there’s no need for a local power source. Two standards exist, providing the option of 12.95 watts or 25.5 watts of power at the device.

Source: Blog.T3innovation.com