Switching Hubs
Switching hubs (aka switches) operate at the Data Link layer of the OSI reference model and increase network performance by reducing the number of packets transmitted to the rest of the network.
Unlike bridges, the switch, opens a virtual circuit between the source and the destination computer.
This prevents communications between two computers from being sent to every computer on the network or segment.
When two machines have a virtual circuit between them, they do not have to share the wire with any other computers.