What is DNS? | What is Domain Name System? | Web Dev Lesson


Hello readers!

Do you want to know, What is DNS, Types of DNS, Its use and How DNS works.

So let's know about DNS in detail.

What is DNS?

The DNS is Domain Name System. DNS converts domain names into IP addresses, which browsers use to load pages on the web.

The domain name system is like the phonebook of the Internet. People get information online through domain names like youtube.com, google.com or webdevlesson.com.

DNS or name System basically translates those domain names into IP addresses and points your device in the right direction.

Each device connected to the web has its own number, using these numbers, these devices find and communicate with one another on the Internet, these numbers are referred to as IP addresses.

What is DNS Server?

A DNS server may be a computer that contains a database that contains the public IP addresses associated with the names of those websites. The site's IP address is what instructs the device to travel to the correct location to access the site's data.

How does DNS work?

You can understand how DNS works in four easy steps: 

Suppose you would like to visit our website www.webdevlesson.com or the other website.

Step-1 : Open a browser on your computer or mobile and sort in the address bar and press enter on the keyboard. If DNA records are found in your computer's DNC cache, it'll skip the rest of the DNS lookups and take you directly to www.webdevlesson.com .

Step-2 : If no DNS records are found, a question is sent to your locale DNS server. this is often usually your Internet provider's server and is often referred to as a "resolving name server".

Step-3 : If the records aren't cached on the resolving Name-Server, the request is forwarded to the basis Name-Server to locate the DNS records. Once the DNS record is found on the basis Name-Server, it's cached by your computer.

Step-4: Now website supported Jambix sites website opens and opens on website.

Why DNS is used?

The global nature of Internet services requires a network of distributed and scalable DNS servers to ensure that users can quickly view and resolve the location of requested servers, no matter where in the world they are.

The purpose of DNS is to translate the domain name into the appropriate IP address. This is done by looking at the DNS records of the requested domain.

Types of DNS Server

  1. Recursive server 
  2. Root Name Server
  3. TLD Name-Server 
  4. Authoritative name server

What is DNS Recursive server?

The recursive resolver (also known as a DNS recursor) is the first stop in a DNS query. The recursive resolver acts as a middleman between the client and the DNS namesever. After receiving a DNS query from the web client, the recursive resolver will either respond with cached data, or send a request to the root nameserver, followed by another request to the TLD Name-Server, and then finally to the authoritative nameserver. 

After receiving a response from the authoritative Name-Server with the requested IP address, the recursive resolver then sends the response back to the client.


During this process, the recursive resolver will retrieve cache information from authoritative name servers. When a client requests the IP address of a domain name that was recently requested by another client, the resolver can circumvent the process of communicating with the Name-Server, and deliver the request record to the client from its cache. 

Most Internet users use the recursive resolver provided by their ISP, but there are other options available; For example Cloud-flare's 1.1.1.1.

What is DNS Root Name Server?

13 DNS root name servers are known for each recursive resolver, and are the first stop in the search for DNS records for the recursive resolver. The root server accepts a query from the recursive resolver that contains the domain name, and the root name server instructs the recursive resolver to search for a TLD name server based on that domain's extension (.com, .net, .org, etc.). Is. Root name servers are maintained by a non-profit organization called the Internet Corporation for Assigned Names and Numbers (ICANN).

Note that when there are 13 root name servers, it does not mean that there are only 13 machines in the root name server system. There are 13 types of route name servers, but there are many copies of each one around the world, which use Any-cast routing to provide quicker responses.


What is a TLD Name-Server?

TLD name servers keep track of all domain names that have a common domain extension, such as .com, .net, or whatever, at the end of a URL with . Come after the dot, share. For example, the .com TLD name servers contain information for each website that ends in '.com'. If a user was searching for google.com, after receiving a response from the root name server, the recursive resolver would then send a query to a .com TLD name server, which would respond by pointing to the authoritative name server for that domain.

Management of TLD nameservers is handled by the Internet Assigned Numbers Authority (IANA), a branch of ICANN. IANA breaks down TLD servers into two main groups:

  1. Generic top-level domains: These are domains that are not country specific, with some of the most well-known generic TLDs being .com, .org, .net, .edu, and .gov.
  2. Country code top-level domains: These include any domains that are specific to a country or state. Examples include .uk, .us, .ru and .jp.

There is actually a third category for infrastructure domains, but it is almost never used. This category was created for the .arpa domain, a transitional domain used in the creation of the modern DNS; Today its importance is mostly historical.


What is an Authoritative name server?

When a recursive resolver receives a response from a TLD Name-Server, it will direct the response resolver to the authoritative Name-Server. The authoritative Name-Server is usually the last step in the resolver for an IP address. 

The authoritative name server has information specific to the domain name it serves (eg google.com) and can provide a recursive resolver with the IP address of that server found in the DNS records, or if the domain has a CNAME record (alias) it will provide the recursive resolver with another domain, the dot (.) at which the recursive resolver is called to retrieve the record from the authoritative name server (often a record containing an IP address) as a whole new DNS lookup has to be done. Cloud-flare distributes DNS authoritative name servers that come with Any-cast routing to make them more reliable.


I hope you have got a good idea about Domain Name System (DNS) from this post.

If you still have any other questions or suggestions regarding this topic, then you can inform us through the comment section.