Switch

A mechanical, electrical, or electronic device that opens or closes circuits, completes or breaks an electrical path, or selects paths or circuits. A switch looks at incoming data to determine the destination address. Based on that address, a transmission path is set up through the switching matrix between the incoming and outgoing physical communications ports and links. A network device that is an intelligent hub because it knows the addresses of the systems connected on each outbound port. Instead of repeating traffic on every outbound port, a switch repeats only traffic out of the port on which the destination is known to exist. Switches offer greater efficiency for traffic delivery, create separate broadcast and collision domains, and improve the overall throughput of data.