14.5 Bridges an internetworking device that connects two similar local area networks that use the same LAN protocols. Performance - enables clustering of devices so that intranetwork traffic significantly exceeds internetwork traffic. Security - different types of traffic can be kept on physically separate media which are connected by bridges. Geography - can be used to connect physically distant devices. 14.6 Layer 2 and Layer 3 Switches Hubs - acts as a repeater.
Repeats signal on the outgoing line to each station.
A hub uses a star wiring arrangement to attach stations to the hub. A transmission from any one station is received by the hub and retransmitted on all of the outgoing lines. Only one stations can transmit at a time. Multiple levels of hubs can be cascaded in a hierarchical configuration. Layer 2 Switch or Switching hub - the central hub acts as a switch.