Power over Ethernet (PoE)
A major advantage of this approach is the elimination of an additional power supply, so that for instance the camera is only connected to the host PC with a single cable. The only component needed is a PoE supporting network unit on the host side.
This makes it possible to install Ethernet connected systems even in narrow or inaccessible spaces, or in areas where the use of many cables would be inconvenient.
There are two Power over Ethernet standards:
- PoE - IEEE 802.3af: power per port 15,4 W, usable power 12,95 W;
- PoE+ - IEEE 802.3at: power per port 60 W, usable power approx. 50 W;
