WHAT IS THE DIFFERENCE BETWEEN HUB, SWITCH AND ROUTER?

 Hub

A Hub is just a connector that connects the wires coming from different sides. There is no signal processing or regeneration. 

Switch

Switch is a point-to-point communication device. It uses switching table to find out the correct destination. Basically, it is a kind of bridge that provides better connections.

Router

Routers are the multiport devices and more sophisticated as compared to repeaters and bridges.

The different between hub, switch and router are A Hub works on the basis of broadcasting. Switch works on the basis of MAC address. A router works on the basis of IP address. A Hub is a multiport repeater in which a signal introduced at the input of any port appears at the output of all available ports. A Switch is a tele-communication device which receives a message from any device connected to it and then transmits the message only to the device for which the message is intended. A router reads the header of incoming packet and forward it to the port for which it is intended there by determines the route. It can also perform filtering and encapsulation.