What Is the Difference Between DNS Server and DNS Client?
When it comes to understanding the Domain Name System (DNS), it’s important to distinguish between the DNS server and the DNS client. Both play a crucial role in translating domain names into IP addresses, but they have distinct functions and responsibilities.
DNS Server
A DNS server is a computer or network device that stores a database of domain names and their associated IP addresses. It acts as a central authority responsible for resolving queries from DNS clients. There are several types of DNS servers, including:
- Root Servers: These servers are at the top of the DNS hierarchy and provide information about top-level domains (TLDs) like .com, .org, or .net.
- TLD Servers: These servers handle queries related to specific TLDs. For example, if you’re looking for information about a .com domain, your query will be directed to a TLD server responsible for .com domains.
- Authoritative Servers: These servers store information about specific domains.
When a query is made for a particular domain, an authoritative server provides the IP address associated with that domain.
- Caching Servers: Caching servers temporarily store recently accessed domain information to speed up future queries. They reduce network traffic by serving cached responses instead of querying authoritative servers every time.
The primary function of a DNS server is to respond to queries from DNS clients by providing the corresponding IP address associated with a given domain name.
DNS Client
A DNS client, also known as a resolver, is any device or software application that initiates a request to translate a domain name into an IP address. When you type a URL into your web browser or access a service by its domain name, it is the DNS client that sends a query to a DNS server.
The DNS client can be your computer, smartphone, or any device connected to the internet. It relies on the services provided by DNS servers to resolve domain names and establish connections with other devices or services.
Generally, when you enter a domain name in your browser, your DNS client follows these steps:
- Local Cache Lookup: The DNS client first checks if it has recently resolved the same domain name and stored the corresponding IP address in its local cache.
- Recursive Query: If there is no cached information available, the DNS client sends a recursive query to its configured DNS server. The recursive query process involves multiple steps and interactions between different DNS servers until the IP address for the requested domain name is found.
- Caching of Response: Once the DNS client receives a response from the DNS server, it caches this information locally for future use. This caching improves performance by reducing subsequent query times for the same domain name.
- Data Transmission: With the resolved IP address, the DNS client establishes a connection with the desired device or service using that IP address.
Conclusion
In summary, while both DNS servers and clients are essential components of the Domain Name System, they serve different roles. The DNS server stores and provides information about domain names and their corresponding IP addresses.
On the other hand, the DNS client initiates queries to translate domain names into IP addresses using services provided by DNS servers. Understanding these differences helps us appreciate how this system enables seamless communication on the internet.