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What is a DNS


Domain Enter Karna:

Jab aap apne browser mein koi website ka naam (e.g., www.google.com) likhte hain, to yeh domain name hota hai.

DNS Query:

Browser pehle yeh pata lagata hai ke is domain name ka IP address kya hai (kyun ke internet sirf IP addresses ko samajhta hai).

DNS Resolver:

Aapka internet service provider (ISP) ka DNS resolver yeh request receive karta hai aur IP address dhundhne ki koshish karta hai.

DNS Servers ke Layers:

Recursive Resolver:

Yeh pehle try karta hai local cache se answer dena. Agar na mile, to Root Server se poochta hai.

Root Server:

Root Server batata hai ke top-level domain (e.g., .com, .org) kahan milega.

TLD Server:

TLD server batata hai ke specific domain (e.g., google.com) ka information kahan hai.

Authoritative DNS Server:

 Yeh final server hota hai jo domain ka IP address provide karta hai.

IP Address Return Hona:

 Resolver ko IP address milta hai aur yeh aapke browser ko deta hai.

Website Open Hona:

 Browser IP address use karke server se connect hota hai aur website load karta hai.

                                 __________

1. Forward Lookup: Kya Hota Hai?

Domain name se IP address find karna.

Example:

Aap www.google.com likhte ho aur DNS se iska IP address milta hai, jaise 142.250.190.78.

2. Reverse Lookup: Kya Hota Hai?

IP address se domain name find karna.

Example:

Aap 142.250.190.78 dete ho aur DNS se iska domain name milta hai, jaise www.google.com.

Short Comparison:

Forward Lookup: Domain → IP

Reverse Lookup: IP → Domain

                                  __________

DNS process ki short example:

1.     Tum Google ka ghar (website) ka address (IP) dhundhne ja rahe ho, lekin address pata nahi, sirf naam pata hai.

2.     Pehle apne area ke office (DNS Resolver) jaate ho. Agar unke paas address hai, turant mil jayega; warna wo aage poochhenge.

3.     City office (Root Server) batata hai ke "Google .com colony mein hai."

4.     Colony office (TLD Server) batata hai ke "Google ke ghar ka detail unke main office (Authoritative Server) se milega."

5.     Resolver finally Google ke main office se exact address le aata hai.

6.     Tumhe address mil gaya aur tum Google ke ghar (server) connect ho gaye!

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