What Is DNS Client and DNS Server?
When it comes to understanding the functioning of the internet, two crucial components that play a significant role are DNS client and DNS server. These components are responsible for translating domain names into IP addresses, making it possible for us to access websites by simply typing their names in the browser’s address bar. In this article, we will delve into the details of what DNS client and DNS server are and how they work together to enable smooth communication on the internet.
A DNS client is a computer or device that sends requests to a DNS server to resolve domain names into IP addresses. Every time you enter a website URL, your computer acts as a DNS client by sending queries to a DNS server to obtain the corresponding IP address.
The process begins when you type a URL in your browser. The browser then sends a request to the operating system’s network stack, which in turn forwards it to the configured DNS resolver. The resolver can be either your ISP’s DNS resolver or a public resolver like Google’s Public DNS or Cloudflare’s 1.1.
The DNS client sends a query message containing the domain name to the resolver, which then searches its cache for the corresponding IP address. If the resolver has previously resolved that particular domain name, it returns the IP address directly without involving any further steps.
If the resolver does not have the requested information in its cache, it acts as an intermediary between the client and authoritative DNS servers.
A DNS server, on the other hand, is responsible for storing and providing information about domain names and their associated IP addresses. It plays a crucial role in resolving queries sent by DNS clients.
DNS servers are organized in a hierarchical structure, where the top-level DNS servers store information about the root domain names like .com, .org, .net, etc. These servers are managed by organizations such as ICANN (Internet Corporation for Assigned Names and Numbers). When a DNS server receives a query for a domain it does not have information about, it contacts the appropriate top-level DNS server to obtain the required information.
Once the DNS server receives the requested IP address from either its cache or another DNS server, it sends the response back to the client through the resolver. The client then uses this IP address to establish a connection with the desired website.
In conclusion, DNS client and DNS server work hand in hand to ensure that we can access websites using domain names. The client sends requests to a resolver, which in turn communicates with authoritative DNS servers to obtain IP addresses. Understanding how these components function together helps us appreciate the behind-the-scenes mechanisms that enable smooth internet communication.