Routers, Types and Functions of Routers

Alfred Ajibola - Thu, 25th July, 2019 @ 14:40: PM

Topics in ICT

Routers, Types and Functions of Routers Computer scheme of work, SS1, First Term Computer scheme of work, SS1, Second Term Computer scheme of work, SS1, Third Term Computer Networks and Types of Computer Network Domain Name System; How DNS works and Types of DNS Servers Internet of Things (IoT), How IoT works, its advantages and challenges How to consume less data on your android phone Best programming languages to learn Internet, Notable Dates and Events on Internet Evolution

Academic Questions in ICT

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A specialized router residing at the boundary of a company's network is called a/an _____.

  • A. Wired Router
  • B. Wireless Router
  • C. Core Router
  • D. Edge Router
  • E. Virtual Router
  • F. LAN Router
  • G. WAN Router

Which of the following is NOT a type of computer network?

  • A. NAN
  • B. MAN
  • C. CAN
  • D. LAN
  • E. WAN
  • F. PAN

The above diagram best illustrate a _____.

  • A. LAN
  • B. WAN
  • C. CAN
  • D. MAN
  • E. PAN
  • F. NAN

The layer 3 device that move packets between devices, allowing Network communication is called a _____.

  • A. Switch
  • B. Router
  • C. Firewall 
  • D. Computer
  • E. Smart phone
  • F. Central Procession Unit

What are Routers?

You are able to get to this website because some networking devices have been strategically positioned somewhere around the world. These devices helps to move or route data from one computer (client computers) to another computer where the information is stored (server). It is important to state that these devices must be properly configured so that sent data (also called packets) can arrive at their proper destinations. (Inside the packets are all the Layers 2 - 7 details of the OSI Model). Please read on the Open Systems Interconnect (OSI) Model here.

The hardware device that moves data (packets) between different devices (clients and servers), allowing network communication are called Routers.

Routers are also called Layer 3 devices. The is because the are found at Layer 3 of the OSI Model.

We find routers in places where connections to networks are required. They are used in banks, campuses, corporate offices, governmental institutions, IT centers and so on.

Now, take a moment to imagine what happens when you visit a bank’s branch in order to check your account statement. What actually happens is:

Behind the scenes, the bank’s branch is connected to its Head Office through some routers. (The routers making this connection should probably be more than 1). These routers have been properly configured by a networking specialist so that communication can happen between the bank’s branch and HQ. When the accountant enters your account number on his/her computer and hits the enter key. (Your account number becomes a part of the data alongside those of layers 2 - 7 of the OSI model). This information is speedily relayed to a router which receives and analyzes the data (preferably called packets). If the information are in sync with the router's configuration, the router forwards it to another router and this process continues until the packets get to the destination server in the bank’s Head Office. When the server sends the reply, a similar process is followed; thanks to the router. Please read on Domain Name Service here to further understand how the internet work.

Image Credit: Route-XP

Note The following points:

It is the function of the router to receive, analyze and route incoming packets to the desired network or destination.

The router can drop packets when some configurations are not properly met by the incoming packets. This is probably why you can't  access the internet from your service provider when you are yet to subscribe for a data package.

A router receives, analyzes and routes incoming packets from it's ingress interface to another network through it' egress interface. It can also drop packets according to it's Quality of Service (QoS) configuration.

Ingress interface is the port on which packets enters the router. Egress interface is the port on which packets exit the router.

Cisco made it's first Router in 1978. Please read on notable dates on internet evolution here

In summary, Routers generally perform the followiing functions.

  1. They ensure that information, data or packets make it to the intended destination.
  2. They separate networks: When the Local Area Network (LAN) becomes too big, traffic speed will be reduced. The router comes to the rescue by separating such large networks; giving rise to internetworks. The term Internet was actually coined from the term internetwork or  internetworking. When you use the internet, you are actually connecting to the network of others. Please read on computer networks here.
  3. They connect networks: For instance, your service provider’s network is able to connect you to the internet through their various routers.
  4. They ensure the security of data: Routers have basic network firewalls within them to carry out their security function.
  5. Routers assist in sharing home Internet connections for multiple home devices

Note: Routers carry out their routing functions by creating a routing table in its memory. Also, Logical addressing are associated with the router.


Types of Router

  • Wired Routers

A wired router connects directly to end devices (e.g computers and VoIP phones) or intermediary devices (switches and other routers) through cables at one end. On the other end, it is connected via a cable to a modem for receiving internet data packets. Wired routers typically supports Network Address Translation (NAT). NAT allows multiple end devices to connect to the internet through a shared single Internet Protocol Address (IP Address). Lastly, wired routers have firewalls built within them to filter traffic (packets) coming from or going to bad destinations.


  • Wireless Routers

Unlike the wired router, a wireless router connects to end devices without any form of cables. To achieve this, it has antennae which broadcast wirelessly; while also receiving signals from end devices. Wireless routers are used for establishing a Wireless Local Area Network (WLAN). They also support NAT and have firewalls within them.


  • Virtual Routers

These are standby routers that commence their function when the active router fails. They function using a protocol called “Virtual Router Redundancy Protocol” (VRRP). Virtual routers are recommended in institutions that push critical data, for instance, financial and medical data.


  • Edge Router or Gateway Router

They can be wired or wireless. They are located at the edge of networks; that is, The last router that connects a company to the internet.


  • Core Routers

They can also be wired or wireless. The are present within the Local Area Network (LAN), distributing data packet within it. For instance, the core routers are responsible for routing traffic between two departments (let’s say human resources and sales departments) within the same organization in the same building.


Alfred Ajibola is a Medical Biochemist, a passionate Academician with over 7 years of experience, a Versatile Writer, a Web Developer, a Cisco Certified Network Associate and a Cisco CyberOps Associate.

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Amazing facts in ICT

Image Credit: Neowin

Smoking near an Apple (Mac) computer voids the warranty.

When you add /4 to the end of Facebook's URL, it will take you to Mark Zuckerberg.

You can try it on you own; or better still, try the link below:



The internet and the World Wide Web (www) IS NOT the same thing. 

The internet is formed from the joining or linking of different networks. 

For instance, Google's network, Facebook's network and Yahoo's network are among the many other networks that make up the internet.

World Wide Web on the other hand is a collection of linked pages (for instance, this page you're on).

There are actually billions of linked pages in various servers around the world.

You require the internet and a web browser to get to the World Wide Web

Please read more on the internet here

Types of Networks Based on Geographical size

  1. Personal Area Network (PAN): An instance is a Bluetooth connection between two devices.

  2. Local Area Network (LAN): This is the network under a single administrative control and usually within a building.

  3. Campus Area Network (CAN): This network connects various devices within a campus or college

  4. Metropolitan Area Network (MAN): This network connects two offices/companies within a city

  5. Wide Area Network (WAN): This network connects devices throughout the globe. The internet is a typical example of a WAN.

You can read more on the types of network based on Geographical Size here