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Aftab Faisal
Aftab Faisal

Posted on • Updated on

DNS - Domain Name System (simplified)


What? 🤔
The Domain Name System (or DNS) converts human readable domain names (like: into Internet Protocol (IP) addresses (like:

Why? 🤔
Computers can only communicate using a series of numbers, so DNS was developed as a sort of “phone book” that translates the domain you enter in your browser into a computer readable IP.

Process ⚙️

☑️ Check your device cache

When you search for a website or web-page , your browser will not know the i.p address of the web server. Your browser will first check its cache memory to see if it has the DNS records for that domain cached. It also checks the hostfile of your computer/mobile for the ip address.

☑️ Check with your ISP

Your ISP (Internet Service Provider) caches popular sites like , , (facebook?), etc. If they have the record in their cache, you would skip the rest of the DNS lookup process.

☑️ Root DNS server & TLD server

Top Level Domains are .com .gov .net .in etc.
Top Level Domain servers have information about the Master/Authoritative DNS servers which actually contain the server information.
Root DNS servers are tasked to find and point to the Top Level Domain Servers.

☑️ Super Fast! ⚡

This entire DNS lookup process happens in just a couple milliseconds. For perspective, we blink our eyes in roughly 50 milliseconds. We can resolve most DNS queries in under 30 milliseconds.👀

☑️ References

  1. DNSmadeEasy

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