Domain Name System – explained in a simple way

The Domain Name System, or DNS, is one of the Internet’s pillars that we utilize every day but don’t realize it. This system is like a telephone directory with the names of people. But instead of a phone, it uses an IP address corresponding to a domain name. 

A brief history of DNS

The Domain Name System was created in 1980 by Paul Mockapetris. Until then, to access a website, you had to enter its IP. Since this process is prolonged and we can’t remember every single IP address, Paul invented the DNS system. To this day, it is the backbone of the internet. 

How does the Domain name system work?

As already explained, DNS binds a domain name to an IP address. It has a hierarchical look and starts from right to left (i.e., from .net.). But what is the process until the IP address is reached? We will now look at this process step by step.

Step 1: A user tries to access a website via a browser, for example, www.dns-reverse.net. The request comes to the DNS resolver (Recursive DNS server). 

Step 2: The DNS resolver sends a query to the Root Servers or Root name servers. These servers contain information about the name servers of each TLD. So it will give us information about .net. It returns information on which TLD server to go to.

Step 3: This information is returned to the DNS resolver. It already knows which nameservers contain information about .net, so it forwards the query to them.

Step 4: The TLD name servers return information about the responsible name servers for dns-reverse.net.

Step 5: The Resolver asks the responsible authoritative name servers if they have information for dns-reverse.net. If they do, they will return the IP address for www.dns-reverse.net (for example, IP address 135.77.148.44). It is the final server and gives information about the configured zones, which makes it fast. 

Step 6: The Recursive DNS server gets the IP and sends it to the web browser. Then the web page loads, and you have now successfully accessed this site through its domain. 

This whole process may seem complicated, but it happens extremely fast, over milliseconds. In addition, DNS information is often cached to reduce response time. A DNS cache is a database on a temporary basis that contains information about the IP addresses of sites you have tried to access. And if the information you are looking for is not cached, then the steps we explained above will be followed. 

Why is the Domain Name System important?

As you may have come to this conclusion yourself, without the Domain Name System, we would not be able to access web pages easily. That means we will have to enter the IP address of the page that we are searching for every time. Furthermore, DNS not only gives us easy access to the Internet, but also makes accessing different pages quick. Thanks to DNS for making it easy and fast for us to obtain the internet. 

Leave a Reply

Your email address will not be published.