EC285 Lecture Notes - Lecture 2: Hypertext Transfer Protocol, Web Hosting Service, 1-Hydroxy-7-Azabenzotriazole
Document Summary
There are 13 advanced computer systems in the world that know (or quickly learn) the ip addresses of all hosts with names of the form: name. tld. Where name is a host and tld is a top-level domain, as in. These 13 systems are called root name servers. If a user directs his or her computer to connect to a remote computer using the remote computer"s domain name, the user"s computer asks the local network"s dns server for the ip address of the remote machine. If the local server knows the address, it supplies it to the user"s machine, and the user"s machine will start sending ip packets to that address. If, on the other hand, the local dns server doesn"t know the ip address associated with the target host name, it will ask a higher level dns server. This process may well continue up to the level of a root name server.
