What Is the Main Function of DNS Server?
When we browse the internet, we often take for granted the complex processes that happen behind the scenes to ensure that we can access websites seamlessly. One such critical process is the functioning of the DNS server.
DNS: Domain Name System
The Domain Name System, commonly known as DNS, is a decentralized naming system for computers, services, or any resource connected to the internet. Its primary function is to translate human-friendly domain names into machine-readable IP addresses.
The Importance of DNS Server
Imagine if you had to remember and enter long strings of numbers such as “192.168.0.1” every time you wanted to visit a website instead of simply typing “www.example.com.” This is where the DNS server comes in; it acts like a phone book for the internet by providing an easy-to-remember name for each website or service.
The main function of a DNS server is to:
- Resolve Domain Names: When you type a URL into your browser, the DNS server translates it into an IP address so that your device can connect to the correct webserver. It acts as a translator between humans and machines.
- Caching: To improve efficiency and reduce network traffic, DNS servers store previously resolved domain names and their corresponding IP addresses in cache memory. This way, when you revisit a website, your browser can quickly retrieve its IP address from local storage instead of querying multiple servers again.
- Distribute Network Load: High-traffic websites often use multiple servers distributed across different locations.
The DNS server helps distribute incoming requests evenly across these servers by providing different IP addresses based on users’ locations. This helps prevent any single server from being overloaded.
- Manage DNS Records: DNS servers also store various types of DNS records, such as A records for mapping domain names to IP addresses, MX records for email routing, and CNAME records for domain aliases. These records are managed by domain owners or administrators to ensure the correct functioning of their websites and services.
Types of DNS Servers
There are several types of DNS servers, each serving a specific purpose:
Root Name Server
The root name servers are the backbone of the DNS system. There are 13 sets of root name servers worldwide, managed by different organizations. These servers contain information about top-level domains (TLDs) like .com, .org, .net, and country-code TLDs like .uk, .fr, etc.
TLD Name Server
Top-level domain (TLD) name servers are responsible for storing information about specific TLDs. For example, if you visit a website with a .com extension, the TLD name server for .com will provide the IP address associated with that domain.
Authoritative Name Server
An authoritative name server holds the actual DNS records for a particular domain. It is responsible for providing the IP address associated with a specific hostname within that domain.
A recursive resolver is an intermediary that receives DNS queries from clients and retrieves the requested information on their behalf. It sends requests to other servers until it obtains a final answer and then returns it to the client.
The main function of a DNS server is to resolve human-readable domain names into machine-readable IP addresses. It plays a crucial role in ensuring that we can access websites and services on the internet effortlessly. By understanding the workings of DNS, we can appreciate the complexity and importance of this fundamental technology.