DNS

Domain Name System (DNS) resolves host names (e.g. jmvidal.cse.sc.edu) into their corresponding IP numbers (129.252.11.88). It is described in a series of RFCs.
IP numbers relate to the physical layout of the network. They are used for routing.
It is hierarchical. Each domain (sc.edu) has its own authority. If it does not know the mapping it will ask a higher domain (.edu) ending in one of the eight root DNS servers. Fro example:
- When your machine hadar.cse.sc.edu needs to know the IP for www.wastingtime.com it will ask your local DNS server (cse). If it does not have it cached, it will ask the next one higher up (sc).
Domain names relate to ownership and responsibility. They are meant to be used by humans.