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Knowledge organisers / Networks and topologies

The Internet: DNS (Domain Name Server)

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Knowledge organiser

Networks and topologies

1.3.1e.i

What you need to know

The Domain Name System (DNS) translates human-readable website addresses (URLs) into numerical IP addresses that computers use to find each other. It acts like a phone book for the Internet.

Key points

  • Definition:DNS (Domain Name System): a system of servers that converts URLs (e.g. www.example.com) into IP addresses that computers can understand.
  • When you type a URL, your computer sends a request to a DNS server to find the corresponding IP address.
  • If the DNS server has the record, it returns the IP address. If not, it queries another DNS server — this repeats until the address is found.
  • Exam Tip:DNS is needed because humans find it easier to remember names (www.google.com) than IP addresses (142.250.187.46).
  • Common Mistake:Saying DNS 'stores websites'. DNS only stores the MAPPING between domain names and IP addresses — it does not store web pages.