This 2025 guide explains how to enable, verify, and optimize PoE on Cisco switches, including standards, power budgeting, configuration commands, troubleshooting steps, and security recommendations. Before enabling PoE, it's important to understand what each standard. Power over Ethernet (PoE) is a technology that transmits both electrical power and network data over an ethernet cable. With PoE, each Ethernet interface of LAN switches can supply power to devices like VoIP phones, IP cameras or security cameras, and wireless access points (AP), As shown in the. The PoE standard specifies the way that power is injected into the Ethernet cable pairs, and which pairs should be used. Power is injected using one pair of wires to carry the positive current (“plus”), and a second pair to carry the negative (“minus”). By eliminating the need for separate power.