(Domain Name Server) is the system used in Internet to be able to
assign and universally use unequivocal names to refer to systems
connected to the net. Thus both human users and applications can
used DNS names instead of the numeric addresses of the IP net. This
represents great advantages, among others the fact that it is easier
and less burdensome for us to use names and not
numbers and it allows an organization to make the name of machines,
services, email addresses etc independent from the specific number
addresses which working systems may have at a given time in function
of changing elements such as the topology of the net and the provider
of access to Internet.
DNS is an immense data base distributed hierarchically throughout
Internet: there are innumerable servers which interact among themselves
to find and provide for the customer applications which consult
them the translation of a name to its associated PI address, to
which the desired connexion may be made. Each part of the data base
has a replica in at least two servers and this
ensures the proper redundancy factor.
reason which motivated the development and implementation of DNS
in Internet was the great growth in the number of machines connecred.
Previously, the link between numbers and IP addresses was made via
lists kept centrally is a single file (Host.txt) which had to be
constantly updated with each new system connected up and to be present
in all the computers connected to Internet.
maintenance of this system became unviable when the number of connected
systems reached a few thousand in the mid 1980s.
is its objective?
objective of DNS is to allow the scaling down, from both the administrative
and technical points of view, of the system of Internet names by
means of a hierarchical distribution of delegated domains. The domains
are administrative entities the object of which is to divide up
the management load of a central administrator and share it out
among the subadministrators. The latter in their turn may repeat
the process if the volume of the domain to be administered makes
the first hierarchical level are the "Top Level Domains"
or TLDs which are one per country (two letter domains which correspond
to the ISO-3166 code for each territory) plus the special 3 letter
domains: "edu", "com", "gov", "mil",
"org", "int" and "net".
general the hierarchical structure of DNS tries to reflect administrative
dependencies administrativas under a first geographical component
(or activity component in the case of the "special" TLDs);
for instance, a machine or service belonging to a department or
branch of an organization in France will have a name of the type:
TLD has its own regulations which say who can and who cannot register
a second level domain, which domains are allowed, which procedures
are to be followed etc. The fact that someone satisfies the requirements
to register a domain under one TLD does not mean that he satisfies
them to register this or another domain under another TLD.
does the STA (ANDORRAN TELECOMMUNICATIONS SERVICE) do?
of the main functions of the ANDORRAN TELECOMMUNICATIONS SERVICE
is to register the names of second and third level DNS domains under
"ad" for use on the Internet by Andorran organizations.
This document contains the regulations and procedures governing
the registration of second and third level DNS domains under "ad".
find out who the contact persons for a second level domain existing
and delegated under "ad" are, you can consult the data
base of the ANDORRAN TELECOMMUNICATIONS SERVICE, EXISTING DOMAINS.