How DNS Resolution Works

Before trying to understand, how the dns resolution works , we need to understand the what do you mean by dns and resolution .

DNS-domain name system

Resolution-finding the solution of the problem

So basically ,Any device in the internet to communicate with each other, we need IP(intenet protocal) address.The example of ip address is 198.51.100.10.just ask a question to yourself , memorizing number is easy or the name .if there is large number of devices , it becomes difficult to memorize the ip address.so its better to memorize the domain name .so the solution of problem is dns resolution.if you give domain name to dns Resolver then the dns Resolver gives you the ip address . once your browser gets the ip address , it can request corresponding web pages.

so we understood the purpose of the dns , now lets understand in detail.

so There are 4 server involved in dns resolution:

1.recursive server:

whenever we search any website in the browser then , this request goes to the recursive server which send of you the ip address of the website . the recursive job request to multiple server to find the ip address. the first request goes to the root server while the last request goes to the authoritative server/

2.root server:

this server returns the adress of tld server like .com,.org etc . based on what request it came to us , address of that tld only.

3.TLD server:

so the recursive server request to tld for ip of the domain name but it return the address NS of domain name.

4.authoritative server:

This is the only server who know the address of the website , it return the ip address to the recursive servive which then return to the browser.