What is a Router & Its Functions?

A router is a layer three device used to connect different networks.

It also connects networks with different network addresses.

The router works in the Network Layer (OSI Reference Model) and connects similar and different types of networks.

Ethernet and FDDI are two different LAN technologies.

We need a router to connect between one FDDI and another Ethernet network.

This tutorial explains the router and its functions.

What is a Router?

A router is an intelligent layer three networking device. It can read and analyze the IP packets sent by other network devices.

A router receives and forwards IP packets by reading the destination addresses.

Do you wonder how a router forwards IP packets? It does it with the help of a routing table and routing protocols.

Let us check how routing tables and protocols assist a router in packet forwarding.

A router makes routing decisions based on the routing table it has.

The routing table consists of path information to send packets to neighboring routers.

A router finds the shortest path to send packets to the destination by calculating the entries in the routing table with the routing protocol.

You have learned about routers and routing tables. Now, let us check the router functions.

We cannot finish an article about routers without mentioning their functions. The primary functions of a router are:

Let us check different types of routers.

According to the guidelines by Cisco, we can classify routers into five categories. They are:

Here we provide links to some of our popular configuration and troubleshooting guides.

You can find some of our recent tutorials below.