Switch is a network device that is used to connect computers that required high bandwidth as well as used to connect hubs to form large network. Switches are more expensive but provide better performance to hubs. As a hub switch also receives data packets, when switch port receives the signal first of all look at the destination address of the frame and establish a connection to th~ destination node. Other ports of the switch are not aware to this interconnections, each port corresponds to individual collision domain which avoid blocking. Whereas Ethernet switches are able of set up multiple internal connections simultaneously. Two types of switches are:
• Layer-2 switches:
These types of switches are based on the Bridging technology. They establish connection between the ports based on the MAC address stored in the address table. These switches fragment existing network into smaller collision domain and improves the performance of the network.
• Layer-3 switches:
These types of switches are based on the routing technology and responsible for set up connection between the ports based on the network address. These switches fragment different network into an internet work. These switches are some time known as routing switches.