Power over Ethernet (PoE) is a technology that allows electrical power and data to be transmitted over the same Ethernet cable, eliminating the need for separate power cables for devices like IP phones and security cameras. PoE technology offers convenience, cost savings, and flexibility, with different standards and types such as active and passive PoE to ensure compatibility and safety.

This chapter discusses Power over Ethernet (PoE) technology, which allows networking devices to receive both power and data through a single Ethernet cable, eliminating the need for separate power cables. It also explains how PoE injectors can convert non-PoE devices to PoE devices, enhancing convenience and reducing costs.

The chapter explains the differences between active and passive Power over Ethernet (PoE), highlighting the importance of matching power requirements to avoid device damage. It also covers the evolution of PoE standards from its inception by Cisco in 2000 to the latest IEEE 802.3bt standard, emphasizing the benefits of PoE in terms of convenience, cost savings, and flexibility.