What is Routing and Switching

In this tutorial, we are going to learn what is routing and switching in the network.

The term routing and switching usually mean, routing or transferring a data packet among multiple networks and switching a data packet between devices in a single network. Routing and switching are the basic things in network communication. These two things perform two different tasks in a network.

When a data packet is sent from one network to another network then it is called "Routing". On the other hand when a data packet is sent from one device to another device under a single network, then it is called "Switching". 

The switching process is executed based on a single network. Its scope of action is within a network. In other words, this switching process is confined to a single network. 

The switching process is the process of transferring or switching data packets between the devices with which a network has been created. Suppose for example a LAN network. The transferring of data among all the devices in this LAN network is called data switching or packet switching. And this packet switching or data switching is done by the network switch hardware. Such as Cisco Switch, Juniper Switch, etc.

This network switch keeps a note of the layer-2 address or MAC address of each device in the network. To put it more clearly,  this network switch saves the MAC address of each device that is connected to its own ports. Then all the information is saved in his own memory in the form of a table. This table is called the MAC table. The MAC table looks like the following:-

Using this MAC table, a switch can easily deliver a single data packet to any device. Because in that case, the switch knows where the destination device is located or which port it is connected to. 

So we can say that the term "switching" is a process that moves a data packet inside a single network.

On the other hand, we can say the "routing" term is a process of route data packets or transfer the data packets in different networks. Such as transfer data between the different LANs. The router devices are used for routing processes. 

Another thing we have to know is that the switching process takes place in layer-2 of the OSI model. And the routing process works in layer-3 of the OSI model. In that case, the switch works in layer-2 of the OSI model hence it is also called a layer-2 device. The router works in a similar way to layer-3, so it is also called a layer-3 device. However, there are some advanced level switches available that work in layer-3 also. Means those advanced level switch can perform the routing functions.