Introduction to Domain Name System (DNS)

Jul 11, 2024

Introduction to Domain Name System (DNS)

Importance of DNS

  • DNS (Domain Name System) is crucial for the functionality of the Internet.
  • Without DNS, modern internet activities (e.g., paying bills online, purchasing goods, streaming music) would be impossible.
  • DNS translates human-friendly domain names into IP addresses, which are used by computers to identify each other on networks.

Basic Functionality

  • The internet is composed of networks of computers communicating via IP addresses.
  • Humans use domain names because they are easier to remember than numerical IP addresses.
  • DNS translates domain names into IP addresses.

How DNS Works

  1. Entering a URL: Typing www.example.com in a browser.
  2. Hidden Dot: Real URL is www.example.com., with a dot at the end, representing the root of the internet’s namespace.
  3. Initial Lookup: Browser checks if it already knows the IP address (in memory or cache).
  4. Resolving Name Server: If not known, the OS asks a resolving name server.
  5. Root Name Servers: If the resolving name server doesn't know, it asks root name servers, which direct it to TLD name servers.
  6. Top Level Domain (TLD) Servers: e.g., COM name servers know where to find the domain’s authoritative name servers.
  7. Authoritative Name Servers: These servers provide the actual IP address for the domain.

Detailed Steps in DNS Lookup

  • Check Cache: System/browser first checks its cache for the domain’s IP address.
  • Resolving Name Server Query: Queries the resolving name server if IP is not cached.
  • Root Name Server Response: Refers to TLD name server (e.g., COM servers).
  • TLD Name Servers Response: Directs to domain’s authoritative name servers.
  • Authoritative Name Server Response: Provides IP address.
  • Final Connection: Browser connects to provided IP address to load the webpage.

Key Points

  • This entire process is extremely quick, taking less than a blink of an eye.
  • Multiple organizations (resolving, root, TLD, and authoritative name servers) are involved in a single DNS lookup.

Significance for Policy Makers

  • Changing any part of the DNS process could be disastrous.
  • Those in power should understand DNS before making legislation changes affecting the internet.

Conclusion

  • DNS is a vital, fast, and efficient system for internet functionality.
  • For more info, visit www.dnsmadeeasy.com.
  • DNS Made Easy has been providing enterprise authoritative DNS services for over 10 years.
  • Benefits include lower costs, increased uptime, and faster speeds.