Domain Name System

The Domain Name System (DNS) is a decentralized Naming System for machines in a network. It’s an Application Layer protocol.

  • Namespace: hierarchical and homogenous
  • There are global and local names.
    • Global: FQDN (Fully Qualified Domain Names), e.g.,
    • Local: e.g., localhost
  • Each context is called a domain
  • Each domain is managed by an authority
  • Impure names
  • Recursive and iterative resolution.