What Is DNS (Domain Name Server)?

What Is DNS – Domain Name Server?

A domain name server (DNS) is the system that manages the names of sites and domains on the internet.

It’s a sort of online phone book, except that the books aren’t located in one physical place. Instead, they are stored on several different servers spread throughout the world.

From emails to websites, DNS is used in nearly every network request and is a vital piece of the internet.

So, how does the DNS work? Let’s explore domain name servers and how they relate to the internet.

What is a DNS Query?

When you type in any web address in a browser, it needs to turn that web address into an IP address so it can contact that web server and deliver the webpage to you. This is an example of a forward lookup, which turns a hostname into an IP address.

Whereas a reverse lookup does the opposite. You type in an IP address and it turns it into a hostname. This process is known as mapping, as it finds a computer’s IP address by using its hostname.

A DNS query consists of the domain name and the type of record it contains. A domain name may appear in multiple records and have multiple IP addresses associated with it.

DNS Protocol

While your computer is a DNS client, a DNS server answers that request. When you want to make a request with a DNS client, it needs to be reliable so data is received correctly with a Transmission Control Protocol (TCP).

TCP is a connection-oriented protocol, where the client and server verify a connection by communicating with each other. By using a 3-way handshake, data can be delivered from server to client.

For transfers of online data, it needs to be routed correctly from server to client. This is why TCP/IP is a fundamental tool on the internet. It provides name-to-address resolution, a service that is essential to TCP/IP networks.

Because of the redundancy that DNS provides, the information in the directory is updated frequently. Also, because there are so many servers, this data is cached locally on individual computers.

Conclusion

A DNS is a service that maps the names of computers on the internet. Like a phone book, DNS resolves human-readable names to IP addresses. When a person tries to reach a website, he or she will use a DNS server. The DNS server will answer the query and then retrieve the site.

It provides name-to-address resolution for TCP/IP-based networks. By using a computer’s hostname, the DNS server can find its IP address using a forward lookup. These processes can take seconds, but they are critical for the integrity of the Internet.