What is DNS?

DNS stands for Domain Name System and it manages the mapping of website names to their corresponding IP addresses. Whenever you type in a web address, your computer will use DNS to look up the IP address associated with that domain name. This process happens in the background and you usually don’t even realize it’s happening. In this article, we will discuss what DNS is and how it works. We will also take a look at the four different DNS servers involved in loading a webpage and examine the steps in a typical DNS lookup.

DNS is a critical component of the Internet and it plays a vital role in how we use the Internet today. Without DNS, we would have to remember long strings of numbers (IP addresses) instead of easy-to-remember domain names. DNS makes the Internet more user-friendly by translating human-readable domain names into machine-readable IP addresses.

How Does DNS Work?

DNS works by breaking down the domain name into smaller parts and then looking up each part in a DNS database. The DNS database is a massive distributed database that contains mappings of domain names to IP addresses. When you type in a web address, your computer will send a DNS query to a DNS server asking for the IP address associated with that domain name. The DNS server will then look up the IP address in its DNS database and return it to your computer. Your computer can then use the IP address to connect to the website’s server and load the website.

The Four Different Types of DNS Servers:

There are four different types of DNS servers involved in loading a webpage:

Root DNS servers: These are the top-level DNS servers that contain mappings for all of the top-level domains (e.g., .com, .net, .org). There are only a handful of root DNS servers in the world and they are all heavily guarded.

Top-level domain (TLD) DNS servers: These DNS servers contain mappings for all of the second-level domains within a particular top-level domain (e.g., .com, .net, .org). For example, there is a TLD DNS server for the .com domain that contains mappings for all of the .com domains (e.g., google.com, yahoo.com, etc.).

Authoritative DNS servers: These are the DNS servers that contain the actual mappings for a particular domain. For example, the authoritative DNS server for google.com contains the mapping for google.com’s IP address. When your computer sends a DNS query for google.com, it will eventually reach google.com’s authoritative DNS server and receive the correct IP address.

Recursive DNS servers: These are the DNS servers that your computer contacts when it needs to resolve a domain name. Your computer will send a DNS query to a recursive DNS server, which will then contact the root DNS servers, TLD DNS servers, and authoritative DNS servers to resolve the domain name. Once the recursive DNS server has obtained the correct IP address, it will return it to your computer.

What Are The Main Steps In A DNS Lookup?

Now that we have a better understanding of the different types of DNS servers, let’s take a look at the steps involved in a typical DNS lookup. When you type in a web address, your computer will take the following steps:

• Step 1:

Your computer will send a DNS query to a recursive DNS server.

• Step 2:

The recursive DNS server will contact the root DNS servers to find out which TLD DNS server is responsible for the domain you are trying to access.

• Step 3:

The recursive DNS server will contact the TLD DNS server to find out which authoritative DNS server is responsible for the domain you are trying to access.

• Step 4:

The recursive DNS server will contact the authoritative DNS server to get the IP address associated with the domain you are trying to access.

• Step 5:

The recursive DNS server will return the IP address to your computer.

• Step 6:

Your computer will use the IP address to connect to the website’s server and load the website.

And that’s how DNS works! By breaking down the domain name into smaller parts and looking up each part in a DNS database, DNS is able to translate human-readable domain names into machine-readable IP addresses. DNS is a critical part of the Internet and without it, we would not be able to access websites by typing in their domain names. Thank you for reading! I hope this article was informative and helpful. If you have any questions, please feel free to leave them in the comments below.