My understanding of DNS
Hi Friends, In this article, I will tell you about my understanding of the DNS server.
What is DNS
The Domain Name System (DNS) is a hierarchical and decentralized naming system for computers, services, or other resources connected to the Internet or a private network. It associates various information with domain names assigned to each of the participating entities. — Wiki.
How does DNS work
When the user enters the URL in the browser address bar it needs to communicate the exact web server where hosted it.
Domain Like www.facebook.com is easy to remember for human but it is not suitable for communication between computers in a network.
In the network, computers can communicate with one another with the unique IP address only.
DNS works like a phone book directory. If we know the domain name we can get the IP address of the domain name. DNS server translates domain name such as www.twitter.com into IP addresses.
When you enter the URL in the address bar of the browser, it searches the IP address using the domain in your local file stored in our PC. If the IP address is not available in your local file then it redirected the DNS server.
In the DNS server first, it directs to the Resolver. Resolver checks first its cache memory. If Resolver could not find, it redirects to the Root Server. The Root server is the top of the DNS hierarchy. The Root server directs Resolver to TLD Server (Top Level Domain server).
TLD stores the address information of Top-level domain such as .com, .net, .org, ..etc. TLD directs Resolver to Authoritative Name Server. Now Resolver asks the Authoritative Name server what is the IP address of www.twitter.com. The Authoritative Name server is the final authority. It will give the IP address of twitter.com. Finally, Resolver tells the computer of the IP address of twitter.com. And Resolver stores the IP address in its cache memory. Because not need to search again.
Thank you for reading. Have a nice day!