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Santhoshi Mary A
Santhoshi Mary A

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how DNS resolver is happening.

When you enter a webpage such as:

Google.com

This name is not understood by your computer.

Only IP addresses such as these are understood by computers:

142.250.190.78

How, then, does your system translate a website name into an IP address?

DNS resolution is the term for that procedure.

Let's take a step-by-step look at it in very basic terms
DNS: What is it?

DNS is an acronym for Domain Name System.

It functions similarly to an online phone book.

👉 You look for a name
👉 DNS provides the IP address (phone number).

For instance:

You enter www.google.com.
DNS provides the Google servers' IP address.
Step-by-Step: DNS Resolution Process
Step 1: Enter a Website

For instance:

Amazon.com

Amazon's IP address is now required by your browser.

Step 2: Check the Browser Cache

Your browser first verifies:

Am I familiar with this IP already?

It might already be stored in memory if you visited recently.

If discovered ->Done
If not, proceed to the following step.

 Operating System Cache in Step Three

Your computer’s OS also keeps a small DNS cache.

If IP is located ->Completed
If not, proceed.
Step 4: Send the DNS Resolver a Request

Your request is now sent to a DNS resolver.

Typically, this is supplied by:

Your Internet service provider, or ISP
or a public DNS such as:
Google Public DNS
Cloudflare (1.1.1.1)

The role of the resolver:

Determine this domain's correct IP address.

Resolver Requests Root DNS Server in Step Five

A Root DNS Server is asked by the resolver:

Where can I locate domains ending in.com?

The root server responds:

Ask the TLD server for.com.

Step 6: Request TLD Server

Top Level Domain, or TLD
For instance,.com,.org, and.net

The resolver queries:

Where is Amazon.com located?

The TLD server responds:

Ask the reputable name server at Amazon.
Step 7: Consult the Authoritative Name Server

The resolver now queries:

What is www.amazon.com's IP address?

The authoritative server responds:

54.xx.xx

Step 8: You Receive Your IP Address Back

The resolver

returns IP to your computer.
stores it in the cache for later use.

Your browser is now aware of the connection location.

 Step 9: Website Loads

Your current browser:

uses IP to connect to the server.
transmits an HTTP request
The website loads

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