Active Ethernet.ppt

Brief introduction POE (Power Over Ethernet) refers to the existing Ethernet cabling infrastructure Cat.5 do not make any changes to the case, for a number of IP-based terminals (such as IP telephones, wireless LAN access point AP, network cameras etc.) to transmit data signals at the same time , but also to provide DC power supply such equipment technology . POE technology to ensure the normal operation of the existing network to ensure the safety of the existing structured cabling while minimizing costs . PoE is also known as LAN-based power supply system (PoL, Power over LAN) or Active Ethernet (Active Ethernet), sometimes referred to as Power over Ethernet , which is using the existing transmission standard Ethernet cable to simultaneously transmit data and the latest standard specification of electric power , and to maintain compatibility with existing Ethernet system and user . IEEE 802.3af standard is based on the new standard Ethernet POE power supply system , which increases the relevant standard power supply via the network cable directly on the basis of IEEE 802.3 , the expansion of the existing Ethernet standards , is the first international on power distribution standards. work process When PSE supply terminal device arranged in a network , POE Power over Ethernet working process is as follows. 1. Detection A beginning , PSE equipment in the port output low voltage cable terminal until it detects a connection to a support IEEE 802.3af standard powered end devices. 2. PD Premises Equipment Category When the receiving end device detects the PD , PSE device may be classified as a PD , and PD devices needed to assess this power loss. 3. Start Power In a configurable time ( generally less than 15μs) start period , PSE equipment starting from a low voltage power supply to the PD device , providing up to 48V DC power supply. 4. Power Supply To provide a stable and reliable 48V DC to PD device , the device does not meet the PD across 15