router

A  that forwards data packets from one local area network (LAN) or wide area network (WAN) to another. Based on routing tables and routing protocols, routers read the network address in each transmitted frame and make a decision on how to send it based on the most expedient route (traffic load, line costs, speed, bad lines, and so on).

Routers are used to segment LANs in order to balance traffic within workgroups and to filter traffic for security purposes and policy management. Routers are also used at the edge of a network to connect remote offices.

Most routers are specialized computers that are optimized for communications; however, router functions can also be implemented by adding routing software to a file server.

Routers serve as an internet backbone interconnecting all networks. This architecture strings several routers together via a high-speed LAN  such as Fast Ethernet or Gigabit Ethernet. Within the global Internet, routers do all the packet switching in the backbones. See also .