What Is DNS Server and How It Works PDF?
Have you ever wondered how you are able to access websites on the internet using domain names like www.example.com instead of complicated IP addresses like 192.168.0.1? The answer lies in the Domain Name System (DNS) and its servers, which play a crucial role in translating human-readable domain names into computer-readable IP addresses.
What is a DNS Server?
A DNS server, short for Domain Name System server, is a computer or network device that is responsible for translating domain names into IP addresses and vice versa. It acts as a directory service, allowing us to easily navigate the internet using familiar domain names rather than remembering long strings of numbers.
When you enter a URL into your web browser, such as www.com, your computer contacts a DNS server to resolve the domain name into an IP address. This IP address is then used to establish a connection and retrieve the requested web page.
How Does DNS Server Work?
The functioning of a DNS server involves several steps:
- Step 1: Request Initiation
- Step 2: Recursive Query
- Step 3: Authoritative Query
- Step 4: Response
When you type a URL into your browser’s address bar or click on a link, your computer sends out a request to the configured DNS server.
If the requested information is not already cached by the DNS server, it initiates a recursive query process. The recursive query starts from the root DNS servers and moves down through multiple levels until it finds the authoritative DNS server for the specific domain.
Once the recursive query reaches the authoritative DNS server for the domain, it retrieves the IP address associated with the requested domain name.
The DNS server sends back the resolved IP address to your computer, allowing your browser to establish a connection with the appropriate web server and retrieve the requested web page.
Advantages of Using a DNS Server
Using a DNS server offers several advantages:
- 1. Human-Readable Domain Names: DNS servers allow us to use easily recognizable domain names instead of complex IP addresses, making it more convenient for users to navigate the internet.
Faster Access: By caching frequently accessed domain names and their corresponding IP addresses, DNS servers can provide faster access to websites, as they don’t have to perform recursive queries every time a request is made.
- 3. Load Distribution: DNS servers can distribute traffic among multiple servers by using techniques like round-robin, helping websites handle high volumes of requests efficiently.
- 4. Fault Tolerance: In case one DNS server fails or becomes unreachable, there are multiple backup servers available to ensure uninterrupted service and prevent website downtime.
DNS servers are essential components of the internet infrastructure that enable us to navigate using familiar domain names rather than complex IP addresses. They play a vital role in translating these domain names into their corresponding IP addresses and facilitate seamless communication between devices on the internet.
Understanding how DNS servers work can help you appreciate the convenience they bring to our online experiences and the efficient functioning of the internet as a whole.