DNS RESOLVER

RESOLVER


A resolver is more like an cache memory which fetches and helps the os for the IP address by asking other DNS servers

The way it works is:

When a request is generated like "example.com"

The client sends this request to OS.

The OS sends this to DNS RESOLVER asking do u know it's IP address.. it checks its memory if available directly gives it..

 If not then it asks the other DNS SERVER for the IP address same like searching  with TOP LEVEL DOMAIN and SECONDARY LEVEL DOMAIN then ROOT.

 When the server is found it takes IP address the same way back to the DNS RESOLVER which first saves in its cache memory first and then give the OS the info.. 

The next time OS when it comes with the same request.. it first checks its cache memory..

 If found the process is less and the fetching becomes faster.

THE WORK FLOW IS:

User --> Resolver --> Root --> TLD --> Authoritative --> IP --> User

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