DNS

• A system to aid humans remember network addresses: Domain Name System

• DNS servers keep mappings of IP addresses and easy-to-remember names:

  • www.cmu.edu. CNAME WEB3.ANDREW.cmu.edu.
  • WEB3.ANDREW.cmu.edu A 128.2.11.43

• Also, aliases of easy-to-remember names for (drums...)EVEN MORE easy-to-remember names

• DNS is a hierarchical, (sort of) distributed system

  • If my DNS server doesn't know an address, it asks its parent DNS server
  • And so on, up to the root DNS servers (that have all the answers)

Notes: