What is DNS and how does it work?
DNS, which stands for Domain Name System, is a system that translates human-readable domain names, such as example.com, into IP addresses, which are used by computers to identify each other on the Internet.
The DNS system is composed of several components, including:
- DNS clients: These are typically your internet-connected devices, such as your computer, phone, or tablet. When you enter a URL into your browser, it sends a DNS query to the nearest DNS resolver.
- DNS resolvers: These are servers that are responsible for looking up IP addresses for domain names. Your ISP or another provider typically provides the DNS resolver. It caches frequently accessed IP addresses, so the queries are resolved more quickly, which saves time and reduces network traffic.
- Root servers: These are the core of the DNS system, and they maintain a database of top-level domain (TLD) servers. They are responsible for handling requests for TLD servers.
- TLD servers: These servers are responsible for resolving queries for domain names with specific top-level domains, such as .com, .net, or .org.
- Authoritative servers: These servers are responsible for holding the IP addresses for domain names.
When you type a domain name into your web browser, the browser sends a DNS query to the nearest DNS resolver, which then forwards the request to the root server. The root server responds with the location of the TLD server for the top-level domain of the requested domain name.
The DNS resolver then contacts the TLD server and requests the IP address for the requested domain name. The TLD server responds with the location of the authoritative server responsible for the requested domain name.
The DNS resolver then contacts the authoritative server and requests the IP address for the requested domain name. If the authoritative server has the IP address in its database, it responds with the IP address, which the DNS resolver then returns to the DNS client.
Finally, the DNS client uses the IP address to establish a connection with the web server that hosts the requested website, and the website is loaded in the browser.
Find more here:
Top comments (0)