The Internet is a global network that is designed to move information. It links billions of devices (desktops, laptops, mobile phones, wristwatches, video game consoles, thermostats, etc.) together all around the world and enables information sharing between them. Let’s see how the Internet works under the hood.
Internet connects devices across the world! So, it must be a very complex system and have a very complex infrastructure! Right? Yes and No. To understand any complex system we hack it into understandable bits. We can follow the same approach to understanding The Internet.
In this article, we will learn about the underlying infrastructure that makes the Internet possible.
The Internet is all about connecting computers with each other. So, let’s start by connecting two computers. We can easily connect two computers with a cable. But can we do the same thing with eight computers? How about a hundred? How many cables and connections would be required to connect all the computers to each other?
If we try to add more computers to this network, the wires required increase enormously. Also, the length of cable to achieve this become quite long if the computers are far away from each other.
This is where we take the help of a special device called the Router. The Router will make sure that the message sent by a given computer reaches the right destination computer.
Let’s connect all computers to a router. The router will now take care of forwarding the message to the right destination computer in our network. Now, if we visualize the network, it becomes quite manageable as it grows bigger.
Our home network is ready now! Oh, wait, how can I connect this network with my friend's network living in another city? 🤔 Can we make use of already existing infrastructure like the telephone network?
For connecting our home network to the already existing telephone infrastructure, we can take the help of a special device called the Modem. The Modem transforms your message into a format that can be transmitted and managed over the telephone infrastructure.
Now our message can travel far! Wow, but wait, I need to send it across the world to another country, how can we do that? 🤔 We take the help of an Internet Service Provider(ISP) for this.
ISPs are organizations that provide services for accessing and using the Internet. ISP manages special routers that connect with other ISPs, thus facilitating information exchange between them. ISPs are further divided into different tiers, we will look into it in a different article.
Our message to a friend in another country would travel from our home network to different ISP networks until it reaches the destination network to our friend’s computer.
Finally, my friend in another country can receive my message. But wait, how are we 100% sure that only my friend’s computer will receive my message and not my aunt’s or some other unknown person connected to the network? We will answer these questions in our next article.