Understanding the Importance of DNS and Why We Use It

Domain Name System, also known as DNS, is a system that enables users to access websites using a human-readable domain name rather than a numerical IP address. DNS is an essential component of the internet; without it, the internet as we know it today would not exist. This blog will discuss DNS, how it works, and why we use it.

What is DNS? 

DNS stands for Domain Name System. It is a system that translates domain names into IP addresses. Every website has an IP address, which is a numerical address that identifies the location of the website on the internet. An IP address is a series of numbers separated by dots, such as 123.456.789.123. However, remembering these numbers is difficult, and it is not practical to expect users to remember them to access websites. This is where DNS comes in.

DNS acts as a translator, converting the human-readable domain name into the numerical IP address that the internet uses to locate the website. The domain name is like the name of a street, while the IP address is like the street’s address. Just as a person needs the address of a place to find it physically, a computer needs the IP address of a website to access it on the internet.

How DNS Works 

When a user enters a domain name into their web browser, the browser requests a DNS resolver to resolve the domain name into an IP address. A DNS resolver is a specialized server that resolves domain names into IP addresses.

The resolver first checks if it already has the IP address for the requested domain name in its cache. If it does, it returns the IP address to the browser, and the browser uses it to access the website. If the resolver does not have the IP address in its cache, it sends a request to the root name servers.

The root name servers are a critical part of the DNS system. There are only 13 of them globally, and they are responsible for directing requests to the correct top-level domain (TLD) name servers. A TLD is part of a domain name that comes after the last dot, such as .com, .org, or .net.

Once the root name server receives a request from the resolver, it responds with the IP addresses of the TLD name servers responsible for the requested domain name’s TLD. The resolver then sends a request to the appropriate TLD name server.

The TLD name server responds with the IP address of the authoritative name server for the requested domain name. The authoritative name server is the server that has complete information about the requested domain name, including its IP address. The resolver then sends a request to the authoritative name server.

The authoritative name server responds with the IP address of the requested domain name, and the resolver caches the IP address for future use. The resolver then returns the IP address to the user’s web browser, and the browser uses it to access the website.

Why We Use DNS 

DNS is an essential internet component because it enables users to access websites using human-readable domain names rather than numerical IP addresses. It also allows website owners to change the IP address of their website without affecting the website’s domain name.

Without DNS, users would have to remember the IP addresses of every website they wanted to visit, which is not practical. Additionally, website owners would have to update their domain names every time they change their website’s IP address, which would be a significant inconvenience.

DNS also provides redundancy and load balancing for websites. When a user requests a domain name, the request is sent to the nearest DNS resolver. The request is automatically redirected to the next available resolver if a resolver is unavailable. This ensures that even if one resolver fails, others can handle the load, and the website remains accessible.

Furthermore, DNS allows for creating subdomains and subdivisions of a domain name. For example, blog.example.com is a subdomain of example.com. This enables website owners to organize their websites and assign different functions to different subdomains. Subdomains can also be used for load balancing, where a single domain name can be associated with multiple IP addresses, each corresponding to a different server. When a user requests the domain name, the DNS resolver randomly selects one of the IP addresses, distributing the load across multiple servers.

DNS is also essential for email communication. When an email is sent, the client uses DNS to locate the mail server responsible for handling the recipient’s email address. This enables email communication to function seamlessly and efficiently.

Security Concerns and DNS 

While DNS is essential for the proper functioning of the internet, it can also be vulnerable to attacks. DNS hijacking is one such attack, where a hacker redirects a user’s DNS requests to a fake website, which appears legitimate but is designed to steal sensitive information, such as passwords or financial information.

DNSSEC (DNS Security Extensions) is a security protocol that adds a layer of security to DNS. DNSSEC uses digital signatures to verify the authenticity of DNS responses, ensuring that users are not directed to fake websites. While DNSSEC is not yet widely implemented, it is becoming increasingly important in securing the internet’s infrastructure.

Last Words

DNS is an essential internet component that enables users to access websites using human-readable domain names. It also provides redundancy and load balancing for websites, enables the creation of subdomains, and is crucial for email communication. However, DNS is also vulnerable to attacks, and DNSSEC is an essential security protocol that adds a layer of security to DNS. DNS is a crucial technology that has revolutionized how we access and interact with the internet. It will continue to play a vital role in shaping the future of the internet.

Frequently Asked Questions (FAQs)