To achieve best performance of a Wireless LAN, the location of Access Point(AP) must be carefully chosen. In most cases, finding a power supply for AP is a common obstacle. Power over Ethernet(PoE) technology provides the ideal power solution to help overcome these obstacles. In Ethernet, four pairs of C5 or C5E twisted pairs are used as the medium for transmission. The actual data transmission, however, only takes up two pairs of wires(pairs 1-2 and 3-6). PoE technology utilizes the remaining pairs(pairs 4-5 and 7-8) to conduct electricity.