How Does DNS Resolve Domain Names to IP Addresses?

Answer: DNS resolves domain names to IP addresses by querying hierarchical DNS servers, starting from the local resolver, root servers, TLD servers, authoritative DNS servers, and caching responses.

Below are the steps describing how DNS resolves domain names to IP Addresses.

Step 1: Domain Name Resolution Request

When the user enters any specific domain name (eg. www.geeksforgeeks.org) in the web browser, the browser sends the DNS resolution request to the local DNS server.

Step 2: Local DNS Resolver

It mainly checks its cache for the IP address corresponding to the domain name. If the IP address is not cached, then the resolver forwards the request to the root DNS servers.

Step 3: Root DNS Servers

The route DNS servers actually has the information regarding to the top level domain servers like .com, .org, .net. If the resolver does not have the IP address, it queries the root DNS servers to get the authoritative DNS server from the specific top level domain DNS server.

Step 4: TLD DNS Server

The TLD DNS server mainly provides the IP address to the Authoritive DNS server.This TLD is mainly responsible for the requested domain.

Step 5: Authoritive DNS Server

The Authoritive DNS server is responsible for the specific domain name which is queued. This Server actually stores the mapping between domain names and ip address in its zone files.

Step 6: IP Address Response

When the Authoritive DNS server receives the query, it responds to the DNS resolver with the IP address for the domain name.

Step 7: Response to Client

The local DNS server sends the IP address back to the client’s web browser.