The need for bridging devices arises with the need to communicate with computers located beyond a particular local area network (LAN). Although all the clients (computers) attached to a LAN need not be located in the same room, there are limitations on the distance between clients as well as on the number of clients that can be attached to a single network segment. Bridging devices are used to overcome these limitations and facilitate communication among machines on different floors, different buildings, different cities, and different countries.

Bridging devices are available in a variety of configurations to interconnect multiple local area network segments. The choice of bridging device depends on distance, traffic volume, and complexity of the communication pathways between sites. Commonly used bridging devices include repeaters, bridges, routers, and gateways.

Repeaters

The simplest bridging device is known as a repeater. As messages travel over...