What is a DNS (Domain Name System)?

What is a DNS (Domain Name System)?

Due to the Domain Name System, surfing the Internet became much simpler. The domain name system functions like a telephone book that provides location and contact details for the methods listed. The location of the website is a numeric internet protocol address. So, in this article, I am going to simplify What is a domain name system and its types.

Domain Name System:

Domain name system is primarily used for a hostname to IP resolution which is not centralized and highly distributed.

On the Internet, computers always identify each other with unique numbers called IP addresses. A domain name system is defined as the place where the Internet domain name is placed and translated into an Internet Protocol (IP) address. The domain name system assigns the names people use to find websites to the IP addresses that computers use to find websites. For example, suppose we humans speak English and we want to communicate with the other person who speaks Chinese. So, for effective communication, we need a translator. Hence, the same in the case of the Internet too. Computers or web browsers only understands the Ip addresses and humans understand our languages say English. Therefore, DNS acts as a translator between humans and the computer.

DNS or Domain Name Systems maintains a table where names are mapped to numbers, or more specifically where websites/domain names are mapped to their IP addresses.

Is DNS Necessary?

Is DNS is necessary

If we know the specific IP address of the website, we can access it by simply typing its IP address in the web browser. In such cases, the DNS will not play any role because we already know the IP address of the website. However, as the number of websites increase, it is difficult to remember IP address. Therefore, the DNS server eliminates the need to memorize complex IP addresses. The only thing we need to memorize are the domain names that are easy to remember.

Working of the Domain Name System:

Before knowing the DNS working process, we need to know the basics of DNS servers. The servers are nothing but computers that store images, HTML files, sounds, videos or any other type of file. The servers that work together to provide the IP address of the requested website to the web browser are called DNS servers.

DNS servers are classified into four types:

  1. DNS recursive resolver
  2. Root name server
  3. Top level domain/TLD name server
  4. Authoritative name server

DNS Resolver:

DNS resolvers are provided by an Internet Service Provider (ISP). It connects our computer’s web browser to a DNS name server.

Root name server:

There are 13 sets of root name servers that are named as letter.root-servers.org. Where letter range is from ‘a’ to ‘m’ and they are operated by 12 different organizations. Each set has a number of servers placed over the world and information page exists for all root name servers at address letter.root-servers.org. Where letter ranges from ‘a’ to ‘m’. But addresses do change. So, the url details of all root name servers can be found in the website root-servers.org.

Top level domain name server:

TLD domain name servers store the information of all domains sharing a common domain extensions(.com, .in, .net, .edu). For example, .com TLD name server stores the information of all websites ending with .com extensions. Likewise, .net TLD name server stores the information of all websites ending with .net extensions.

Authoritative name server:

This is the last server in the Domain name system. This saves the IP address of the requested website. Authoritative name servers for websites can be found using CMD commands such as

  1. nslookup
  2. set query=ns
  3. example.com(domain name)

Domain name system is client/server communication systems, if you type www.xyz.com from your computer here the request is sent and the response comes from the DNS server. Requests that contain names, which generate IP addresses returned from the server, they are called forward DNS lookups, requests that contain IP addresses & generate names called reverse DNS lookups.

Benefits of Domain Name server:

  1. The users can remember friendly domain names instead of IP addresses.
  2. Domain names remain the same even if the IP address changes.
  3. Forward or reverse lookups are possible.
  4. Distributes architecture is fast, resilient.
  5. Easy to update and maintain.
  6. DNS is more reliable, faster, smarter.
  7. DNS can increase the security of your DNS infrastructure, this can allow dynamic secure updates.
  8. Easy to categorize, archive & help search engines.

By the above information you got a brief idea about Doamin Name system and its working.

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