What happens when you type holbertonschool.com in your browser and press Enter?

5 min readSep 2, 2021

Or any other web site…

Well the truth is a somewhat extensive but interesting process and in this blog we will see how that process is and each part which makes it possible these are.

But hey, that’s a lot of questions, I know, but let’s look at them one by one as best we can, well let’s start wth the basics, in each subtitle you will find a link to a much more complete article about the concept we are going to see.

¿What is a TCP/IP?

The current foundational protocols in the suite are the Transmission Control Protocol (TCP) and the Internet Protocol (IP).

An IP address is a set of numbers which each device that is connected to the internet has an IP address, from the cell phone or computer that you are reading the article to your smart TV has its own IP address, therefore the numbers will always be different.

You will find a large set of ip address types such as:

Consumer IP addresses
Private IP addresses
Public IP addresses
Dynamic IP addresses
Static IP addresses

if you are curious or interested in knowing what your ip address is, see it here. :)

Now that we have an idea of what the IP address is, let’s see what TCP is.

The Transmission Control Protocol (TCP) is one of the main protocols of the Internet protocol suite. It originated in the initial network implementation in which it complemented the Internet Protocol (IP).

¿How TCP works?

TCP has a very simple operation consisting of three phases. In the first, the connection is established with the authorization of both parties. Then, a procedure called ‘three-step negotiation’ takes place. This is followed by the transfer of information. Here, each of the parameters for an orderly, correct and, above all, secure exchange are established. Finally, a ‘four-step negotiation’ completes the connection between client and server.

Firewall

A firewall is a security device — computer hardware or software — that can help protect your network by filtering traffic and blocking outsiders from gaining unauthorized access to the private data on your computer.

¿What is HTTPS?

Hypertext transfer protocol secure (HTTPS) is the secure version of HTTP, which is the primary protocol used to send data between a web browser and a website. HTTPS is encrypted in order to increase security of data transfer. This is particularly important when users transmit sensitive data, such as by logging into a bank account, email service, or health insurance provider.

¿What is an SSL certificate?

An SSL certificate is a digital certificate that authenticates a website’s identity and enables an encrypted connection. SSL stands for Secure Sockets Layer, a security protocol that creates an encrypted link between a web server and a web browser.

Companies and organizations need to add SSL certificates to their websites to secure online transactions and keep customer information private and secure.

Load Balancer

A load balancer acts as the “traffic cop” sitting in front of your servers and routing client requests across all servers capable of fulfilling those requests in a manner that maximizes speed and capacity utilization and ensures that no one server is overworked, which could degrade performance. If a single server goes down, the load balancer redirects traffic to the remaining online servers. When a new server is added to the server group, the load balancer automatically starts to send requests to it.

Web Server

A web server is software and hardware that uses HTTP (Hypertext Transfer Protocol) and other protocols to respond to client requests made over the World Wide Web. The main job of a web server is to display website content through storing, processing and delivering webpages to users. Besides HTTP, web servers also support SMTP (Simple Mail Transfer Protocol) and FTP (File Transfer Protocol), used for email, file transfer and storage.

Application server

An application server is a server that hosts applications.

Application server frameworks are software frameworks for building application servers. An application server framework provides both facilities to create web applications and a server environment to run them.

Database

A database is a collection of information that is organized so that it can be easily accessed, managed and updated. Computer databases typically contain aggregations of data records or files, containing information about sales transactions or interactions with specific customers.

DNS request

A DNS query (also known as a DNS request) is a demand for information sent from a user’s computer (DNS client) to a DNS server. In most cases a DNS request is sent, to ask for the IP address associated with a domain name. An attempt to reach a domain, is actually a DNS client querying the DNS servers to get the IP address, related to that domain.

If you like drawings I recommend this comic in which they explain quite well how the DNS works.

How DNS works

A comic that explains what happens when you browse to a website.

howdns.works

Now that we have understood these concepts we can answer the question ¿What happens when you type holbertonschool.com in your browser and press Enter?

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