Security

What is DNS?


DNS stands for Domain Name Service.

Our people use a name to identify each other and they use numbers IP addresses to identify each other in a network.

When everyone logs into a site, we use the web address of that site. For example – Google.com but this website hosts the internet as an IP address eg – 172.217.194.113. So those letters Google.com cannot be identified by these internet servers. Therefore, as a solution to this problem, network engineers have created a system called DNS

When you type google.com in your browser, the DNS will look for a matching IP address in your database. Like finding out.


Here is what happens. When we first type google.com, if the browser does not find our web browser or OS, the computer sends a query to the next level, that is, to the resolver server. The resolver server is your internet service provider. . This resolver server then checks its cache to see if there is an ip address that matches google.com. If he can find it, he will send a query to the next level. That is the root server. At the top of the dns hierarchy is the root server.


There are 13 sets of root servers. Installed in various places around the world. Operated by 12 organizations.

When the resolver query is sent to the root server, the root server does not know what the relevant IP address is. .Now Resolver asks for the ip address of google.com from the TLD server. Store the TLD server for address information, top level domain. Examples: – .com, .NET, .ORG etc.


We have (manage) the TLD server we are considering. Only the COM domain. Google.com is the same. But we do not know this TLD serve. What is the ip address that matches google.com. Then the TLD server redirects the resolver to the last level or the last server.

That is the Authoritative Name Server. Resolver asks him ip address in google.com. Authoritative Name Server He knows everything about a domain including ip address. This is the last one. He sends the last ip address of google.com to resolver.

Then resolver says this is the ip address for your pc. Now the pc can retrieve the google web page.

Once he gets a resolver ip address he will store it in the cache. Then you don’t have to go that way again from the beginning

Leave a Reply

Your email address will not be published. Required fields are marked *