A network switch is networking hardware that connects devices on a computer network by using packet switching to receive, and forward data to the destination device. A network switch is a multiport network bridge that uses media access control addresses to forward data at the data link layer of the OSI model.
A POE switch is a network switch that has Power over Ethernet injection built-in. Simply connect other network devices to the switch as normal, and the switch will detect whether they are POE-compatible and enable power automatically.
A media converter is a device used to connect media that would otherwise be incompatible. It is used to link fiber optic cable to twisted pair for supporting ethernet-compatible devices. It may also link together networks comprised of coax cable, and single-mode to multi-mode fiber optic cable.
Small form-factor pluggable, or SFP, devices are hot-swappable interfaces used primarily in network and storage switches. The SFP ports on a switch and SFP modules enable the switch to connect to fiber and Ethernet cables of different types and speeds.
A router is a device that forwards data packets along networks. A router is connected to at least two networks, commonly two LANs or WANs or a LAN and its ISP's network. Routers are located at gateways, the places where two or more networks connect.