Bridges

The bridge function is to attach separate homogeneous networks. Bridges map the Ethernet address of the nodes residing on each network segment and allow only essential traffic to pass by the bridge. When a packet is received by the bridge, the bridge verifies the destination and source segments. If the segments are dissimilar, then the packet is "forwarded" to the correct segment. Bridges are also known as "store-and-forward" device because they look at the whole Ethernet packet before making filtering or forwarding decisions.