Skip to main content

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!

Comments

Post a Comment

Popular posts from this blog

TCP/IP MODEL

  HISTORY OF TCP/IP MODEL THE TCP/IP MODEL WAS DEVELOPED BY VINT CERF AND BOB KAHN IN THE 1970S. THEY WERE BOTH WORKING AT THE DEFENSE ADVANCED RESEARCH PROJECTS AGENCY (DARPA) AT THE TIME. Vint Cerf And Bob Kahn CERF AND KAHN WERE TASKED WITH DEVELOPING A NEW NETWORK PROTOCOL THAT WOULD BE MORE RELIABLE AND EFFICIENT THAN THE EXISTING PROTOCOLS. THEY CAME UP WITH THE IDEA OF USING A LAYERED APPROACH, WHICH WOULD ALLOW EACH LAYER TO FOCUS ON A SPECIFIC TASK. THIS LED TO THE DEVELOPMENT OF THE TCP/IP MODEL, WHICH IS STILL THE BASIS FOR HOW DATA IS TRANSMITTED OVER THE INTERNET TODAY. CERF AND KAHN ARE OFTEN REFERRED TO AS THE "FATHERS OF THE INTERNET" FOR THEIR WORK ON THE TCP/IP MODEL. THEY WERE INDUCTED INTO THE NATIONAL INVENTORS HALL OF FAME IN 2004 FOR THEIR CONTRIBUTIONS TO THE DEVELOPMENT OF THE INTERNET. HERE ARE SOME OTHER NOTABLE PEOPLE WHO CONTRIBUTED TO THE DEVELOPMENT OF THE TCP/IP MODEL: JON POSTEL: POSTEL WAS THE FIRST CHAIRMAN OF THE INTERNET ENGINEERI...
Post a Comment
Read more

Types Of Attack in Network

Common Network Attacks Explained. 1. Overwhelming a Network (DoS/DDoS): Imagine a restaurant that's flooded with too many customers. In a DoS/DDoS attack: A website is overwhelmed with too much traffic. 2. Eavesdropping on Conversations (MitM): Imagine someone listening in on your phone call. In a MitM attack: An attacker listens to your online conversations. 3. Tricking You (Phishing): Imagine receiving a fake email from your bank. In phishing: Attackers try to trick you into giving them your personal information. 4. Finding a Weakness in a Website (SQL Injection): Imagine finding a hole in a fence. In an SQL injection attack: An attacker finds a weakness in a website to steal or change data. 5. Planting a Hidden Camera (XSS): Imagine someone hiding a camera in a party. In an XSS attack: An attacker hides harmful code on a website to spy on you. 6. Guessing Your Password (Password Attck): Imagine trying to guess a friend's password. In a pas...
Post a Comment
Read more

OSI Refrance Model

OSI MODEL 1. THE OSI MODEL WAS DEVELOPED BY THE INTERNATIONAL ORGANIZATION FOR STANDARDIZATION (ISO) IN THE LATE 1970S. THE MAIN ARCHITECT OF THE OSI MODEL WAS HUBERT ZIMMERMANN, A FRENCH SOFTWARE ENGINEER. 2.  ISO REPRESENT A 1947 MORE THAN WORK AND AGAIN REPRESENTS A ISO IN 1977 AND MORE THAN WORK AN REPRESENT  IN 1983 A OSI REDFRENCE MODEL. 2. HIS MODEL REPRESENT A 7 LAYER 3. OSI MEANS  (OPEN SYSTEMS INTERCOMMUNICATIO). 1. APPLICATION LAYER 1. THE APPLICATION LAYER IS USED BY END-USER SOFTWARE SUCH AS WEB BROWSERS AND EMAIL CLIENTS.  IT PROVIDES PROTOCOLS THAT ALLOW SOFTWARE TO SEND AND RECEIVE INFORMATION AND PRESENT MEANINGFUL DATA TO USERS. 2.  IT SENDS ITS DATA TO THE FORM OF THE  PDU. PROTOCLS  AND DEVICES USED IN LAYER THERE ARE SOME PROTOCOLS THAT WORK AT THE BACKEND OF THE APPLICATION LAYER. WHICH IN TURN WORKS AT THE APPLICATION LAYER. MANY DEVICES USE IT AT THE APPLICATION LAYER. PROTOCOLS FTP  (FILE TRANSOFER PROTOCOL) DNS (DOMA...
Post a Comment
Read more