$ Domain Name System (DNS)
(I) The main Internet operations database, which is distributed
over a collection of servers and used by client software for
purposes such as (a) translating a domain name-style host name
into an IP address (e.g., "rosslyn.bbn.com" translates to
"192.1.7.10") and (b) locating a host that accepts mail for a
given mailbox address. (RFC 1034) (See: domain name.)
Tutorial: The DNS has three major components:
- Domain name space and resource records: Specifications for the
tree-structured domain name space, and data associated with the
names.
- Name servers: Programs that hold information about a subset of
the tree’s structure and data holdings, and also hold pointers
to other name servers that can provide information from any
part of the tree.
- Resolvers: Programs that extract information from name servers
in response to client requests; typically, system routines
directly accessible to user programs.
Extensions to the DNS [R4033, R4034, R4035] support (a) key
distribution for public keys needed for the DNS and for other
protocols, (b) data origin authentication service and data
integrity service for resource records, (c) data origin
authentication service for transactions between resolvers and
servers, and (d) access control of records.