What is Domain Name System (DNS) | How DNS Works | DNS Server full Details

What is Domain Name System (DNS) |  DNS Server Full Details:

What is Domain Name System (DNS)?

The Domain Name System is also called short in DNS. DNS server is to convert the domain name to an IP address. When we type any domain name in a web browser, this DNS converts it into an IP address. 

Similarly, any computer and hostname in any of these networks also convert to these IP addresses. This is because we can remember Alphanumeric Name easily as compared to the IP address. 

For example - when we type www.example.com in the browser then the DNS has a valid value of it in or similar. Changes to the IP address. Now you see yourself, how easy it is to remember us www.example.com, how difficult it is to remember an IP address.

Now we know that there can be countless DNS and IP addresses in the case of Public IP Address, then only one server cannot save all the information, that's why when the query comes to a server and that server's IP address If he does not know or if he does not solve the query then he sends the query to another server connected to it. This pass on continues until the query resolves and the IP address is not found.

DNS implements a distributed database to store this name and address information for all public hosts on the Internet.

DNS (Domain Name Server)

DNS is a protocol of the standard set that determines how data will be exchanged over the Internet and other private networks, known as the TCP / IP protocol suite.

The URL of any web site is like www.google.com, but in reality, every domain name behind this URL is assigned an IP address.

What is Web Address? How does the URL work?

Its basic work is the Internet Protocol (IP) address of any user-friendly domain name such as www.google.com and it is used by the computer to identify each other on the network.

Computers and other network devices on the Internet route the request you have given using an IP address to open the web site.

This is exactly the same as you call your phone by dialing a phone number. But due to DNS, you do not have to remember the IP address of each site. You just have to remember the name of that web site.

So when you type in the name of that web site in your browser, you connect to the Domain Name Server, which also goes to DNS, which manages a huge database, in which each domain name has its IP address Are mapped to

The DNS server matches the domain name with the corresponding IP Address. When you type a domain name in your browser, your computer contacts your current DNS server and asks how the IP address is connected to the domain name. Your computer then connects to an IP address and opens the right web page for you.

Google DNS: Domain Names and IP Addresses

The Domain Names website contains such addresses, which we can remember and use every day. As Google's domain name is google.com and you have to go to Google, then you enter google.com in the address bar of your web browser.

However, your computer does not understand where "google.com" is. Because the Internet and all other networks use Numerical IP addresses, such as This IP address is for google.com.

If you type this number in the address bar of your web browser, you can visit Google's website.

But we use google.com instead of because we can easily remember addresses such as Google.com.

How does DNS work?

Whenever an internet user visits a domain like techndaily.com, your computer or smart device moves several steps that convert the human-readable web address to a machine-readable IP address.

Whether you are accessing the web site or sending an e-mail, your computer uses a DNS server to look up the domain name you use. This process can be called DNS Name Resolution.

DNS Steps:

  • You type the google.com domain name in the browser of the Windows or Apple OS operating system.
  • The client should know its IP address where on google.com the locale is located. (Usually, all websites are hosted in an internet data center)
  • Your browser will send this query to the PC operating system.
  • Each operating system is configured to query some DNS servers. Typically, your ISP or network administrator configures a DNS server called a Resolving Name Server.
  • The person who resolves this name server is not aware of the location of google.com, but he knows where the root server is.
  • Next, the Resolving Name Server searches the location of the top-level domain name serve and sends a query to google.com. Each domain on the Internet has an official name server.
  • Finally, this official name server will give you the exact IP address of google.com. This information will be returned to the Resolving Name Server, which caches this information and sends the anchor to the browser.
  • In most cases, there are two DNS servers, one primary and one secondary server. These are automatically configured when connecting to your ISP on your router and/or computer via DHCP.
  • You can configure two DNS servers, one of which fails when the other server is used.
  • Some DNS servers have faster access times than others, but it depends entirely on how long it takes on your device to access the DNS server.
  • If you are experiencing network related issues where it seems that no websites are loading, then there is a problem with the DNS server.
  • If the DNS server is not able to find the correct IP address of the hostname you entered, the website will not load.

Domain Name Space:

A namespace maps each IP address with a unique name. Whenever a website or server is assigned a name, it is selected from the namespace itself. A namespace can be organized into 2 types. These are being given below.

Flat Name Space

This type of namespace contains a name that is mapped with an IP. It is not a centralized namespace, so it cannot be used for the internet. Because this leads to the problem of creating duplicate domain names.

Hierarchical Name Space

The domain names you use today are allotted with a similar namespace. In this type of namespace, domain names are composed of several parts. Just as one part tells which type of organization this domain name is related to, another part can tell the name of the organization or information related to it.

For example, at www.example.com domain name com states that it is commercial and is giving information about an example of a company.

 The implementation of the hierarchical namespace is the domain namespace. The domain namespace is represented in the form of a tree, which contains a root server. Other servers are also in this hierarchy. When a server is unable to resolve a name, it passes the request to another server in the tree.

Domain name space hierarchy

There are 2 types of domain names in the domain namespace. These are being given below.

Fully Qualified Domain Names

A fully qualified domain name is one that is separated by dots (.). Every dot operator represents a different hierarchy level. The example of such a domain name is given below.


Partially Qualified Domain Name

A partially qualified domain name does not contain dots. In such domains, there is only one node name and it does not grow on the root side like fully qualified domain names. The example is given below.

DNS (Domain Name System) Servers Full Details:

DNS (Domain Name System) consists of 3 types of servers.
  1. Root server
  2. Primary server
  3. Secondary server

These three servers work on different hierarchy levels of the domain namespace. In the context of the Domain namespace hierarchy, their diagram is given below.

Root server

A root server is a server whose zone has a full domain namespace hierarchy. This server maintains a master zone file, which contains information about all other zones. A root server does not hold any information about domains.

This server maintains the start of authority and acts as the starting authority for other servers. First, the request comes to this server which is then passed to other servers.

Primary server

A primary server maintains a file related to its zone. Primary servers are also called top-level domain servers. Primary servers are many such as com, gov, in, etc. All these are maintained as different servers. Primary servers have 3 tasks.

  • Create Zone File
  • Maintain Zone File
  • Update Zone File

Secondary server

The secondary server transfers information about the zone of another server. Secondary servers are also called authoritative servers.

This information is transferred to a secondary or primary server. A secondary server cannot create and update zone files. It only provides information about the authority related to the domain.

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Working of DNS (Domain Name System):

The working process of DNS (Domain Name System) is explained below step by step.

1. First, the user writes the URL of a website in the address bar of the web browser and presses enter. For example, the user wants to open www.techndaily.com.

2. The browser first checks its cache whether it already has an IP address for this domain name. Whenever you visit a website, its IP address browser stores it in a few days for your chance. This is done so that the same process should not be repeated repeatedly and not load on the server.

3. If the browser gets an IP address in the cache then the user is connected to that IP address and the website loads.

4. If the browser does not find the IP address in its cache, then the browser transfers it to the OS (Operating System). The operating system transfers this request to the resolver.

5. Resolver checks its own cache for the IP address of this domain name. If the IP address is found, the resolver transfers it to the OS and the OS web browser.

6. If the resolver does not get an IP address, it passes this request to the root server. A resolver is your ISP (Internet Service Provider). All resolvers have information about the root server.

7. Root server passes this request to the top-level domain server. Top-level domain server has information about com, gov, edu, org, etc, etc

8. Therefore it passes this request to the appropriate top-level domain server. For example, in the case of techndaily, this request will be passed to the com server.

9. The top-level domain server passes this request to the authoritative name server. In the process of so far, the com server has been located, now the actual name server will be located.

10. Whenever a domain is registered, the domain registrar stores that domain name and shares this information with the top-level domain servers. Therefore, the top-level domain server knows where the actual name server is.

11. The authoritative name server provides the IP address of the domain name requested. Resolver stores this IP address in its cache. In addition, the OS also stores this IP address in its cache to serve the further requests.

Finally, the resolver loads the website into the browser at the base of the IP address.

Configuring DNS (Domain Name System):

The domain name system can be configured in 2 types.
  1. As local hosts files
  2. As a centralized DNS server
Both these methods are being given in detail below.

As Local Hosts Files

When you configure the domain name system as local files, you have to statically configure each translation (from domain name to IP address) on every device.

In Windows operating system, this file is located in c: windows system32 drivers, etc hosts directory. In a Linux operating system, this file is located in the, etc / hosts directory.

There are several disadvantages to configure DNS as a local hosts file, which is being given below.

DNS is statically configured on every device, so this is a time-consuming process.
If a change is to be made, then this change will have to be done manually on every device.

As a Centralized DNS Server

It is much better to configure DNS as a server instead of being configured as a localhost file. All devices send a request to this central server for name resolution.

The advantage of keeping DNS as a centralized server is that any change has to be performed in one place.

 If a DNS server does not pass the required information, then the request is sent in the DNS hierarchy to the server above it.

Configuring DNS on Cisco Devices

As I mentioned above, DNS is configured in 2 ways. You can also configure name resolution in both of these methods on Cisco devices.

You can type the command in this manner to build a host table manually on Cisco devices.

Router (config) # IP host host-name IP-address
This is explained by the following example.

Router (config) # IP host router1
To see the Local hosts table, you can type the command as follows.

Router # show hosts
You can write a command like this to point an iOS device to a centralized DNS server.

Router (config) # IP name-server
To disable the DNS lookup on any iOS device, you can type this command.

Router (config) # no IP domain-lookup
You can type the command in this way to configure a local domain on an iOS device.

Router (config) # IP domain-name techndaily.com


What is a DNS server?

The Domain Name System (DNS) is a technology standard for managing public web sites and other Internet domain names. As soon as you type a website named www.google.com on your web browser.

DNS Computer allows your computer to automatically detect the website on the Internet. The basic functionality of DNS is based on a worldwide collection of DNS servers.

A DNS server can be a computer registered to join the domain name system.

A DNS server runs special-purpose networking software and includes a database of network names and addresses for other Internet hosts.

DNS root server (DNS ROOT SERVERS)

DNS servers communicate with each other using the private network protocol. 

All DNS servers are organized in a hierarchy. At the top level of the hierarchy, there is a root server that stores a complete database of Internet domain names and their associated IP addresses.

The Internet has 13 root servers that function based on their particular role. These servers are maintained by various independent agencies.

Ten DNS servers are employed in the United States, one in Japan, one in London, one in the UK, and one in Stockholm.

How does DNS work?

DNS is a distributed database system. There is a complete database of only 13 root server names and addresses.

Your ISP also keeps its own DNS server installed.

DNS is based on client/server network architecture. Your web browser acts as a DNS client (also known as DNS resolver). It sends requests to its Internet service provider's DNS servers while navigating between web sites.

Types of domain

If seen, the domain name is very different, but today I will tell you about them in all the ways that are very important. So whenever you choose a domain name you can easily get it done.

1. TLD- Top Level Domains

Top Level Domains (TLD) 

We are also known as an internet domain extension. This is the last part where the domain name ends. The area after Dot was first developed. With the help of this domain, you can easily rank your website. It is very SEO friendly and it also gives more importance to Google Search Engine.

Example TLD Extention By which anyone can buy

  • .com (commercial)
  • .org (organization)
  • .net (network)
  • .gov (government)
  • .edu (education)
  • .name (name)
  • .biz (business)
  • .info (info)

example google.com, techndaily.com, facebook.com etc.

2. CCLTD- Country Code Top Level Domains

This type of domain is usually used to keep a particular country in view. It is named on the basis of the two-letter ISO CODE of a country. For example, some important Domain Extention has been given.

  • .us United States
  • .in India
  • .ch Switzerland
  • .cn China
  • .ru Russia
  • .br Brazil

What is a subdomain name?

You may have come to know what the domain name is, but the subdomain is a fraction of your main domain name. The subdomain is not purchased if you have purchased any Top Level Domains Name, then you can divide it into Subdomain Name

Like techndaily.com is my TDL Name and I can divide it into info.techndaily.com. You do not have to give any charge for this, it is absolutely free.

Well, there are other types of Domain Name, but generally, we do not use them to create a Blog / Website.

note: All American Servers use top-level domains with three-letter (eg ".com", ".edu") but other countries use only two letters or two combinations of two letters except America. (eg ".au", ".ca", ".co.jp").

Top Domain Name Provider List:

If you want to create a website for yourself or for your business, then you can also buy a domain name yourself, but for that, you will have to buy a new and unique domain name by registering an account in the domain from a good domain name service provider. 

Below I have given a list of some top Domain Providers for your convenience. You can choose any of these.
  • Bigrock
  • GoDaddy
  • Com
  • Namecheap

note: ICANN (The Internet Corporation for Assigned Name and Numbers) is an organization that authorizes these Domain Providers to sell Domain Names.

How to Create a Domain Name?

1. Always choose a Short Domain Name which is easy to remember.

2. Keep a domain name that is easy to remember, type, and speak.

3. If the domain name is not similar to any other, then it is very unique, which you can easily brand.

4. Do not keep special characters such as hyphen and numbers as possible in this name.

5. Always check to take the Top Level Domain so that all the people in the world recognize it.

6. Your domain name should be related or similar to your business or business profile, this will make it easy to create a brand.

 I always help my readers on every side, if you have any doubt in any way, then you can comment to me, I will definitely reply.

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