- This article is about the network device for computers. For the woodworking tool, see Router (woodworking).
A router is a computer device which aggregates the network needs of many computers, and distributes bandwidth from a central broadband connection. They are classified as layer-three devices on the OSI model.
A router works by having a unique address on each port and a map of the network in an internal table. The router reads a packet from an incoming port, looks it up in the table, and sends it out the appropriate port. Routers use IP addresses to communicate, and also to isolate broadcast traffic.
There are a number of protocols for managing the network address tables of the routers.
A bridge is similar to a router but no address table is used. All traffic in one port goes out the other port.