How Does The Internet Work — Simplified

We consume the Internet for many different purposes such as:
communicating with our loved ones, sending emails at work, binge watch Game of Thrones or even playing the new Justin Bieber song.

We are using different navigation apps to find our way back home after a long night at a birthday party or when we are hungry we order pizza from Domino’s online, and if we’re in a hurry for an important meeting, well…
we can order an Uber.

We are using the Internet every day, and even when we’re not, the internet is all around us.

But do we know how the internet works?

*Please note that in this article I am only covering the basics.

“The Internet is the first thing that humanity has built that humanity doesn’t understand, the largest experiment in anarchy that we have ever had.”
— Google’s former CEO, Eric Schmidt

Few simple principles to begin with

Let’s do it

ISP

Internet Service Provider (ISP) — is an organization that provides services for accessing the Internet.

Server

A server is a special computer connected directly to the internet. Web pages and media are files on that server hard drive/SSD.

Client

Home computers are called ‘Clients’, and they are connected indirectly to the internet through an ISP.

IP address

Every device connected to the internet is identified uniquely by a string of numbers known as Internet Protocol (IP) Addresses. Type “My IP” on Google to see your IP Address.

DNS

Domain Name System (DNS) — is the Internet’s phonebook. To access the Internet, people use domains, such as google.com. Web browsers interact through IP addresses. The DNS is a server that translates domain names to IP Addresses so that the browser can load Internet resources.

Packet

Any piece of information that travels across the internet, is being broken down into smaller pieces of 0’s and 1’s by the computer. These pieces of 0’s and 1’s are called ‘Packets’. When the information reaches its destination, the packets reassemble into their original order.

Router

A router is a networking device that directs the packets around the Internet, helping each packet get one step closer to its destination.

And what about the Internet?

The Internet is simply a wire buried under the ground. It’s as simple as that.

“The Internet is becoming the town square for the global village of tomorrow.”
— Microsoft’s former CEO, Bill Gates

How Does It Work?

The secret revealed

When we type in a web address, our request is being transferred through the router into our ISP. Then, it is being transferred to the Internet and into the server. Once we are connected to the server, we have access to the corresponding web page.

Let’s try an example: Let’s say we want to visit google.com.

1. We open our browser, and we type Google’s domain name (google.com).

2. The browser then sends a request to the DNS server to get the corresponding IP Address. In our case, the IP address of google.com is 216.58.204.14 (you can try and access Google by typing this IP address on your browser).

3. After getting the IP address, our browser simply forwards the request to the receptive server. In our case, Google’s server.

4. Once Google’s server gets an access request, the server sends us the corresponding files as packets.

So this is how it works

“I think most of the important stuff on the Internet has been built. There will be continued innovation, for sure, but the great problems of the Internet have essentially been solved.”
— SpaceX and Tesla CEO, Elon Musk

How are we not getting another person’s request?

Let the magic begins

Now that we know how to access the Internet, let’s take it one step further.

Let’s imagine that we are sitting at a cafe with our best friend, drinking a good cup of coffee, while we’re both surfing the Internet on our smartphones. Besides us, there are many more people surfing the internet on their own devices as well.

While we are using the Internet, we are sending endless packets back and forth. The question is: what keeps the packets in order?

What prevents our request to google.com for example, to appear on our best friend’s smartphone screen? In short — the IP addresses and routers.

As we know, everything that is being connected directly or indirectly to the Internet has an IP Addresses. Our computer, smartphone, servers, and even routers — all have IP addresses.

Hey, packet! from this way…

If we go back to our example, when you visit google.com, a large number of routers help our packet find their way into and from our smartphone. In a way, a packet consists of several layers:

1. The first layer for this example is our smartphone’s IP address.

2. Our smartphone sends the packet to the first router, which adds its IP address.

3. Each time a packet reaches a new router, another layer is added until it reaches Google’s server.

4. When Google’s server sends the corresponding files back to our smartphone, it warps it with identical layers.

5. As the packet makes its way across the Internet and back to our device, each router unwraps a layer to discover where to send the packet next, until it reaches our smartphone (and not our best friend’s smartphone).

To summarize:
The router is navigating the packets into its destination

---

Congratulations!
Now you know the basics of how the Internet works.

• If you find this article helpful, don’t hesitate to share it with your friends!

• You are welcome to follow me on twitter for future articles: Itamar Rosenblum

He knows what he is talking about

Want to learn more about the Internet?

• Video: How the Internet Works in 5 Minutes
• Video: How does the INTERNET work? | ICT #2
• MDN: How does the Internet work?

Bonus resource:

Submarine cable

TeleGeography: Submarine Cable Map — Interactive map of the world’s major submarine cable (Internet’s undersea cable) systems.