Bridge is a device that allows computers on different network or separate segments of the same network to exchange information using the same protocol. Bridge also filters the data or inspects incoming signals and decides whether to forward or discard them.
- It examines the MAC address of each packet. If the packet is destined for a node connected to a different port, the bridge forward the packets and if the packet is addressed to a node on its own segment, the bridge does not forward the packet. This arrangement reduces traffic between segments and improves overall network performance.
- One of the physical properties of an Ethernet is that all computers share the same electric wire. Therefore computers compete to have access of the wire for communicating. If two computers attempt to transmit data at the same time a collision event occurs and the computers keep vying for control of the Ethernet until one wins out. It becomes obvious that collisions increase with the quantity of computers on a LAN to the point where the entire network can be drastically bogged down. Bridges attempt to solve this problem be dividing the network in separate collision domains.