DNS (Domain Name System) operates at which OSI layer?

DNS is responsible for resolving human-readable domain names (like www.example.com) into IP addresses (like 192.0.2.1) that computers can use to identify each other on the internet or a private network.

Here how DNS works in simple steps:

• The user types a web address into their browser.


• The browser asks DNS to find the IP address linked to that domain name.


• DNS looks through a database of domain names and their corresponding IP addresses.


• Once it finds the correct IP, it sends it back to the browser.


• The browser then uses that IP to connect to the website.

Key Points about DNS:

• DNS makes it easier for users to access websites without remembering IP addresses.


• It acts like a phonebook for the internet.


• DNS queries use the UDP protocol by default (port 53), and sometimes TCP for larger responses.

Conclusion: DNS is a core part of the internet and works at the Application Layer of the OSI model. It provides name resolution services that make user-friendly web browsing possible. This makes DNS a very important topic for both interviews and networking exams.