DNS: The Internet’s Address Book

DNS, or Domain Name System, is often referred to as the “phonebook of the internet.” Just as you’d look up a name in a phonebook to find a phone number, computers use DNS to turn human-friendly domain names (like google.com) into IP addresses (like 172.217.5.110) that they use to identify each other on the network.

How Does DNS Work?

1. Query: When you type a URL into your browser, it sends a query to a DNS server asking for the IP address associated with that domain name.

2. Resolution: The DNS server goes through a process of resolution, starting from the top-level domain (like .com or .org) and working its way down to the specific address of the server hosting the domain.

3. Response: Once the DNS server finds the correct IP address, it sends it back to your browser.

4. Connection: Your browser then connects directly to the server at that IP address to retrieve the web page.

Why is DNS Important?

• Usability: It’s much easier for humans to remember google.com than 172.217.5.110.

• Flexibility: If a website changes its IP address, the domain name can stay the same. Only the DNS record needs to be updated.

• Load Balancing: Large websites might have multiple IP addresses. DNS can distribute visitors to different servers to balance the load.