The role of Bridge Versus Switch in networking
A bridge is a product that joins a Local Area Network or LAN to another local area network that applies the same protocol such as token ring or Ethernet. You can visualize a bridge as a device that determines whether the message you sent to somebody will go to the local area network in your building or to someone on the local area network in a building 2 blocks from you.
It analyzes every message on a local area network. It passes those messages that are known to be within the same local area network and then forwarding those messages that are identified to be on the other interconnected local area networks. Node addresses or computers have no particular association with location in bridging networks.
Because of this, messages are delivered to each address on the network and received only by the intended target node. Bridges are capable of learning which addresses are on which network and create a “learning table” so that succeeding messages can be sent to the correct network.