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What is DNS? How Domain Name System works

You might want to go to, but you’ll need to remember a Web address like Is it more complicated? to remember the IP address of every website you want to visit, We are humans, and we are not good at remembering numbers, despite the fact that we can remember a name, such as, so it is easier for us to remember a name rather than an IP address, but computers do not understand names; they only understand logical addresses, such as and DNS, or Domain Name system, plays an important role in resolving this issue. In this blog, we will look at how DNS works and why it is important.

What is DNS?

As we all know, DNS stands for domain name system. It is a translator or mediator that allows us to search a website without having to remember its IP address. DNS maintains a record in which he has the IP address of every domain that exists on the internet and whenever you search for a website like It will provide you with the IP address for that specific website, and you can access the result.

Domain Hierarchy

There is a concept known as domain hierarchy, it is similar to a tree structure in which domains are classified into different subcategories, such as

  1. TLD(Top-Level-Domain:-For example, so here (.com) is known as TLD or we can say Top-level Domain. there are two types of TLD. 
  2. gTLD (generic top-level domain ):-The gTLD was intended to tell us the purpose of the domain name, such as .com for commercial purposes, .org for organizations, .edu for education, .gov for government, .mil for military, and so on.
  3. ccTLD(Country code Top level domain):-ccTLD was intended to indicate the geographical purpose of a domain name. for example .in for an Indian website, .ca for a Canadian website, for a United Kingdom website, and so on. 

There are other new gTLDs domains ranging like .onilne, .biz, .fire, .go, and many more Click here 

Second-Level Domain

For example, here second-level domain will be (allsafesecure), We can say that the left-hand part of the website’s name is known as the second-level domain. It has some limited characters, such as up to 63 characters, and in TLD we can only use (a-z, 0-9, and hyphens)


Now there is something known as a subdomain, such as, where (login) is the subdomain, allsafesecure is the second level domain, is the top level domain.

DNS Server Roles

  • Local DNS Server:-When you make a domain name request. Your computer will first check its local cache to see if you have previously looked up the address; if not, it will send a request to your Local Domain name server and obtain information from there. which is provided by your ISP (internet service provider)  

  • Root DNS servers:- The root DNS server is the father of the Domain Name System, as root servers act as the internet’s backbone, redirecting you to the correct Top Level Domain server based on your request, for example, The root server will recognize the top-level domain of (.com) and redirect you to the correct TLD server that deals with (.com) addresses, so for example, Dot(.)is the root domain, and (.com, .edu, .gov) are top-level domains (Children of root domain)
  • Top-Level Domain Server TLD:-This server keeps a record of all top-level domains such as (.com, .edu, .org, .mil), and whenever they receive a request for any TLD domain such as, they will redirect that request to the appropriate authoritative server to answer the request.
  • Authoritative Server:-We can call this a database for top-level domains, such, which will have its own authoritative server to answer .com-related queries. authoritative server will have all of the information about all of the websites that use TLD, so if you have a query about, so root DNS will redirect that request to the .com Top-level domain and .com top-level domain will find the information about in his authoritative DNS server

Note :- all TDLs have there own seprated authoritative dns server

What happens when you make a DNS request?

So, whenever you make a new DNS request, it first goes to your local DNS server, which is provided by your ISP (internet service provider), and if your local DNS server has the IP address of the DNS request, it gives you the IP address and your work is completed.

But, if your local DNS server does not have the IP address of your DNS request, that request is passed to the root DNS server, and the root DNS server will check your TLD, such as what TLD is used in the DNS request, such as whether it,.edu,, and then after confirming the right TLD, the root server will pass the DNS request to the right TLD server, and the TLD server will check the DNS request in there appropriate authoritative server, and after finding it will give you respond quickly and next time you don’t need to follow this long process

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