A Power over Ethernet (PoE) switch is a network switch that has built-in Ethernet injection capabilities. This means the PoE switch can let Ethernet cables supply power to network devices over the existing data connection. PoE is a networking feature defined by the IEEE 802.3af and 802.3at standards, and the cables commonly used for PoE are Cat5e and Cat6 Ethernet cables.
The latest update to PoE is the PoE+. It can provide almost twice as much power as PoE over a single Ethernet cable.
Simply connect your network devices to the PoE switch, and the switch will detect and automatically enable power if the devices are PoE compatible. PoE switches, based on their configuration, can transmit 10, 100, or 1,000Mbps of data, 15, 30, 60, or 90W of power from a maximum distance of 100m.
Since PoE switches transmit both power and data over a single cable, it cuts down the cost of buying separate cables for each.
PoE switches allow installing network devices like IP cameras anywhere, such as a ceiling or tower, giving greater flexibility for network cabling.
Most PoE switches are SNMP-enabled. This makes monitoring and managing them easy.
The distance is limited to 100 meters, which, in some cases, simply isn't enough. In such cases, power extenders or powered fiber cables are required.
Some devices are incompatible with PoE switches. There are workarounds available, but they are complex and difficult to apply.
Common products that use PoE are IP cameras, VoIP phones, wireless access points, LED lighting fixtures, industrial control system components, and point of purchase kiosks.
8, 12, 24, and 48 port PoE switches are commonly available in the market. Common PoE switches are Cisco Catalyst 2960 48, Cisco SG200-08P 8-Port Gigabit POE smart switch, NETGEAR 16-Port Gigabit Ethernet unmanaged PoE switch (GS116LP), and Netgear GS308P-100NAS Gigabit Ethernet unmanaged switch.