POE is also known as a local area network power supply system (POL, Power over LAN) based on Ethernet or active (Active Ethernet), sometimes also referred to as Power over Ethernet, which is transmitted using the existing standard Ethernet cables for transmitting data and The latest standard specification for electrical power and maintains compatibility with existing Ethernet systems and users. The IEEE 802.3af standard is a new standard based on the Power over Ethernet (PoE) system. It adds the standard for direct power supply through the network cable based on IEEE 802.3. It is an extension of the existing Ethernet standard and the first international standard for power distribution. standard.
IEEE in 1999 began to develop the standards, manufacturers are involved in the earliest 3Com, Intel, PowerDsine, Nortel, Mitel and National Semiconductor. However, the shortcomings of this standard have always restricted the expansion of the market. Until June 2003, the IEEE approved the 802.3af standard, which specifies power detection and control issues in remote systems and provides access to IP phones, security systems, and wireless LANs over Ethernet cables to routers, switches, and hubs. The way in which devices are powered by points is specified. The development of IEEE 802.3af includes the efforts of many corporate experts, which also allows the standard to be tested in all aspects.