What happens when you type an URL in your browser and press enter
By: Juan Camilo Cadavid Velásquez
Tags: Internet, Web, Servers

In this article, I’ll explain to you what’s happening under the hood when you browse the internet.

Let’s break down all the parts that make up an URL, we’re going to take https://www.holbertonschool.com as an example. First, we have the HTTPS protocol, which allows the fetching of resources such as HTML documents, this protocol is the foundation of data exchange over the internet. Second, we have the sub-domain WWW, which can help us split our site into logical parts. After the sub-domain, we have the domain name holbertonschool which is a string of characters that maps to an IP address, and finally, we have the top-level domain .com which is intended to help classify the feature of a site.

The internet explained in a very simple way is a lot of computers connected through a cable that can be underground or underwater, these computers have IP addresses and to communicate with each other computer A needs to know computer’s B IP address.

DNS

Here’s when the Domain Name System comes into play, or DNS as the cool kids call it. The DNS purpose is to translate domain names like www.holbertonschool.com into IP addresses, humans aren’t really good at remembering long strings of numbers, so we just assign a name to an IP so that we can remember it easily. In this case, www.holbertonschool.com translates to 18.204.177.203.

TCP/IP

This stands for Transmission Control Protocol, and this bad boy is in charge of encapsulating data and delivering it to other servers through the internet, to do this, TCP adds layers of information to packages of data to make sure it is delivered the way it should be delivered.

Firewall

Firewalls are used for filtering internet traffic to prevent malicious or useless data from getting into a client or server, Firewalls can be installed on a device or they can also run on their own device, in other words, Firewalls can be physical and or software-based.

HTTPS/SSL

Remember when we broke down an URL? Well, this section will dive deeper into what HTTPS means, it stands for Hypertext Transfer Protocol Secure, which basically means that the data that you send and receive from a site with this protocol will be encrypted. We also have SSL which stands for Secure Sockets Layer, it is a certificate that creates an encrypted connection between you and a site.

All the previous sections help us understand how data moves through the Internet, and now we will learn about how it gets to a server besides, we’ll talk about how it is managed when it gets there.

Load-balancer

Our request has now reached holbertonschool’s load-balancer, the purpose of a load-balancer is to distribute requests to servers using a specific algorithm, it will make decisions on what request goes to each server.

Web server

A web server is a computer that stores the components for a website and it accepts requests via the HTTP protocol or its secure variant HTTPS. It is in charge of running the website, it also distributes web pages as requested by the client.

Application server

An application server installs, operates, and hosts applications and services that the end-user might need, this section sits between the web server and the database.

Database

A database is an organized collection of information and it is connected to the application, the end-user will be able to access information in the database, upload it and delete it through the application, you can also set up different databases and link them to manage data more efficiently using several servers.

That’s it, thank you so much for reading my blog, I hope you learned something.