What is the difference between Hub, Switch, and Router?

Hub operates on the first layer of the OSI model, unlike switches that operate on layer 2 and even on higher standards of the OSI models. They cannot process second or third layer traffic. As already mentioned, the second layer deals with hardware addresses and the third layer with IP addresses where the switches come to use.

Switches work on hardware addresses to exchange data across the devices that are connected to them. Hence, hubs can’t process any information based on MAC or IP addresses. Adding to this, Hubs cannot even process data based on if it is broadcast, unicast or multicast data. In contradiction to this switches first, perform broadcast and then unicast.

One advantage that it has is that Hub can transfer data to every port, but then again it can’t transfer data to the port where the data was generated. Hubs only work in half-duplex mode. Also, collisions can happen. In case a collision does happen, hub rejects all the data from all the devices then signals them to send the data again.

Bridge and switch are different in a way that a switch forwards data at wire speed as it uses ASICs that are special hardware circuits. Switches support full duplex data transfer communication. Switches cannot be used in large networks that are divided into sub-networks because they cannot forward networks or database. Using spanning tree protocol, switches can avoid loops as well. Switches can have unlimited ports because switches don’t divide speed like hubs.

Routers, unlike switches and hubs, operate at the third layer of OSI models. Due to these, routers can forward data across networks. Routers are very rich in features when compared to switches. They maintain a routing table for data forwarding. They also have lesser port densities if compared to switches.