The domain name system (DNS) is like a phone book for the internet. It translates a human-readable domain name, like google.com, into an internet protocol (IP) address, like 74.125.200.101, that computers use to identify each other on the internet. Here’s how it works:
1. A user types a URL (Uniform Resource Locator), like google.com, into their web browser.
2. The browser sends a request to a DNS resolver, which is typically provided by the user’s Internet Service Provider (ISP) or a third-party DNS service.
3. The resolver searches its database for the correct IP address associated with the domain name.
4. If the resolver doesn’t have the IP address, it sends a request to a DNS root server, which directs the resolver to the appropriate top-level domain (TLD) server (.com, .org, .net, etc.).
5. The TLD server directs the resolver to the authoritative name server for the specific domain name (e.g. google.com).
6. The authoritative name server provides the IP address for the domain name back to the resolver.
7. The resolver sends the IP address back to the user’s browser.
8. The browser then sends a request to the appropriate server using the IP address, and the website is displayed.
This process usually happens in a matter of milliseconds, allowing users to quickly access websites without having to remember long strings of numbers.