Switch is a small device that joins multiple computers together of a low-level network protocol layer. Technically, Switch operates at layer two, that is, data link layer of the OSI Model.
Switches looks nearly identical to Hubs, but Switchitch generally contains more intelligence than hub. Unlike hubs, Switches are capable of inspecting the data packets as they are received, determining the source and destination address of the Packet and forwarding that Packet appropriatly.
By delivering messages only to the connected device that it was intended for, that is, signals are transmitted only to the port where they need to go, rather than to all ports unlike hun.
Typrs of Switch :
There are therr basic types of Switch :
1> Cut-Through Switch.
2> Store-and -forward Switch.
3> Fragment free Switch.
Cut-Through Switch :
A Cut-Through Switch forward the Packet as soon as it is received. No error checking is performed on the Packet, so Packet is moved through very quickly. This typw of Switch is relatively inexpensive and minimizes the delay incurred during the processing Packets by the Switch.
Store-and -forward Switch :
In Store-and -forward configuration, the Switch waits to receive the entire Packet before beginning to forward it. It performs basic error checking. This type of Switch is a shared-memory Switch, which has a comman memory buffer that stores the incomming data from all the ports.
Fragment free Switch :
Fragment free Switch works by reading only the port of the packet that enables it to identify fragments of a transmission.