Active Communication

Power over Ethernet or PoE technology describes a system to transfer electrical power, along with data, to remote devices over standard twisted-pair cable in an Ethernet network. This technology is useful for powering IP telephones, wireless LAN access points, network cameras, remote network switches, embedded computers, and other appliances where it would be inconvenient, expensive (mains wiring must often be done by qualified and/or licensed electricians for legal or insurance reasons) or infeasible to supply power separately. The technology is somewhat comparable to POTS telephones, which also receive power and data (although analog) through the same cable. It doesn't require modification of existing Ethernet cabling infrastructure.

There are several general terms used to describe this feature. The terms power over Ethernet (PoE), power over LAN (PoL), and inline power are synonymous terms used to describe the powering of attached devices via Ethernet ports.

There are several PoE implementations, including ad-hoc techniques, but using the IEEE standard for supplying power over Ethernet is strongly recommended.

Video Surveillance with Lantech Industrial PoE Switches

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