A computer science problem by Ashish Sharma

A bridge has a foot in each network and acts on the link layer (level 2). It is able to pass frames from one network to another in an intelligent manner. A bridge, after a period of learning, is able to identify MAC addresses of nodes on each side of the bridge. It prioritizes the frames that actually need to be transferred, so that the traffic on each side is best. A bridge is very effective if the two networks A and B hardly communicate with each other; otherwise, it is best to communicate with an Ethernet cable for example.

A bridge device filters data traffic at a network boundary. Bridges reduce the amount of traffic on a local area network (LAN) by dividing it into two segments.

Bridges operate at the data link layer (Layer 2) of the OSI model. Bridges inspect incoming traffic and decide whether to forward or discard it. An Ethernet bridge, for example, inspects each incoming Ethernet frame - including the source and destination MAC addresses, and sometimes the frame size - in making individual forwarding decisions.

Bridges serve a similar function as network switches that also operate at Layer 2. Traditional bridges, though, support one network boundary (accessible through a hardware port), whereas switches usually offer four or more hardware ports. Switches are sometimes called "multi-port bridges" for this reason.