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.

Router and Routing Table

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.

Examples of Routing Protocols

  1. Interior Gateway Routing Protocol (IGRP)

  2. Routing Information Protocol (RIP)

  3. Address Resolution Protocol (ARP)

  4. Internet Control Message Protocol (ICMP)

  5. Dynamic Host Configuration Protocol (DHCP)

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

Functions of a Router

We cannot finish an article about routers without mentioning their functions. The primary functions of a router are:
  1. Router Connects Different Network Types.

  2. It joins networks with different network addresses.

  3. It finds the shortest path to send packets to the destination.

  4. It defines logical address schemes.

  5. The router supports VLANs.

  6. The router has features like Quality of Service and Filtering.

  7. It builds routing tables to make layer three decisions fast.

Let us check different types of routers.

Different Types of Routers

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

  1. Core router

  2. Edge router

  3. Distribution router

  4. Wireless router

  5. Virtual router

Links to Router Configuration Guides

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

  1. How to Configure Belkin Wireless Device By Manual Steps

  2. Configure D-Link DIR-865L Amplifi Cloud  5700 With Cable & DSL

  3. How to Setup D-Link Wireless

  4. Setup D-Link WiFi WBR-2310

  5. How to Configure Linksys E4200 Wireless-N

  6. Manual Steps to Setup Any Model Of Linksys Routers

You can find some of our recent tutorials below.