DNS - Domain Name System
Guys, how about the world with only IP addresses? Ever wondered if you have to open google.com but instead of this simple URL, you have to type in its IP address every time? In fact for all the web-sites you use, you have to use its IP address to open it up. How the life would be? So just give it a thought.
This is the importance of DNS (Domain name system).
What is DNS
Domain Name System is undoubtedly a central part of Internet, providing a way to resolve a series of numbers to a name. Every device say mobiles, laptops, tablets, phablets, computers, watch connected to internet has got its own unique series of numbers called as IP address that locates the device over the internet. For example you laptop has got an IP address 192.168.12.134 (click to find your IP address), obviously it is very hard to remember. Also if you think of remembering one IP address, there are hell lot of IP addresses you go to everyday. How many will you remember? Here is when DNS comes into picture. You are typing google.com in your browser, but in backend it is calling its IP address that you don't even know & the page will be opened ready for you to access. This is what DNS does in your daily life.
How DNS works
DNS is based on client server architecture. DNS client (any internet user) send requests to and receive responses from DNS servers. Requests called containing a name, that result in IP address being returned from the server, are called forward DNS lookups. On the other hand Requests containing IP addresses and resulting in a name are called as reverse DNS lookup. DNS functions on a distributed database to keep these names and last known address information for all public hosts over the internet.
When client like web browsers issue requests involving internet host names, it first contacts the DNS server to find its IP address, if the current server doesn't have the IP address it will automatically forward it to next DNS server. After several forwardings the IP address for the given host eventually resolves & come back with an opened page on the clients side.
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