conclusion in this area was that the current "user@host" mailbox
identifier should be extended to "email@example.com" where "domain" could
be a hierarchy of domains.
J. Postel; Computer
Mail Meeting Notes, RFC
805; 8 Feb
The Domain Name System was originally
invented to support the growth of email communications on the ARPANET,
and now supports the Internet on a global scale.
Alphabetic host names were introduced on the ARPANET shortly
after its creation, and greatly increased usability since alphabetic names
are much easier
numeric addresses. Host names were also useful for development
of network-aware computer programs, since they could reference a constant host
name without concern about changes to the physical address due to
network alterations. Of course, the infrastructure of the underlying
based on numeric addresses, so each site maintained a "HOSTS.TXT"
between host names
and network addresses in a set of simple text records that could be easily
read by a person or program.
It wasn't long before people realized that keeping multiple copies
of the hosts file was inefficient and error-prone. Starting with a formal proposal
606, in December, 1973, proceeding
Names On-Line, RFC
608, and further discussions in Comments on On-Line Host Name Service, RFC
623, it was settled
by March, 1974 with On
Line Hostnames Service, RFC
625, that the Stanford
Research Institute Network Information Center (NIC) would serve as the
official source of the master hosts file.
This centralized system
worked well for about a decade, approximately 1973 to 1983.
However, by the early 1980's
the disadvantages of centralized management of a large amount
of dynamic data were becoming apparent. The hosts file was becoming larger,
the rate of change was growing as the network expanded, more hosts were downloading
entire file nightly, and there were always errors that were then
propagated network-wide. Change was required, but a spark was needed.
As described in Computer Mail Meeting Notes, RFC
it was initially the need for a real-world solution to
the complexity of email relaying
that triggered the development of the domain concept. A group of ARPANET
researchers, principles, and related parties held a meeting
1982, to discuss a solution for email relaying. As described
email addresses page, email was often
originally sent from site to site to its destination along a path of systems,
and might need to go through a half a dozen or more links that would connect
at certain times of the day. For example, the following actual communication
path shows individual systems separated by "!", with the destination
user named "grg" tagged on at the end.
To send an email to someone,
you had to first be a human router and
specify a valid path to the destination as part of the address. If you
valid route, the software couldn't help you. In order to solve
this problem, domain names were created
to provide each person with one address regardless of
where email was sent from. As RFC
805 put it, "The hierarchical domain type naming differs from source
while the latter gives
RFC 805 outlines many of the basic
principles of the eventual domain name system, including the need for top
for delegation of queries, the need for second level domains to be unique --
and therefore the requirement for a registrar type of administration,
and the recognition that distribution of individual name servers responsible
for each domain would provide administration and maintenance advantages.
Within the year, the concept was developed through a series of communications.
In March, the hosts table definition was updated with DoD
Internet Host Table Specification,
RFC 810, and NIC's introduction
of a server function to provide individual host name / address translations
was described in Hostnames
811, both documents including the domain concept. In
Domain Naming Convention for Internet User Applications,
RFC 819, provided an excellent
overview of the concept. And then, in October, the full concept of a distributed
system of name servers, each serving its local domain, was described
in A Distributed System
for Internet Name Service, RFC
830, providing the main architectural outlines of the system still
in use today.
By the following November, 1983, the concept and schedule were developed
and published in
The Domain Names Plan and Schedule, RFC
Names -- Concepts
And Facilities, RFC
882, and Domain Names -- Implementation And Specification, RFC
Some of the technical
discussion involved in developing the DNS was carried out on the namedroppers list.
BIND. Because the DNS is such a fundamental
part of the operation of the Internet network, the software that runs it must
be nearly fault
free, easily upgraded when a bug is found, and completely trusted by the
Internet community -- in other words, free
open source software.
runs almost every DNS
is called BIND, for Berkeley Internet Name Domain, first
developed as a graduate student project at the University of California
at Berkeley, and maintained through version 4.8.3 by the university's Computer
Systems Research Group (CSRG). The initial BIND development team consisted
of Mark Painter, David Riggle, Douglas Terry, and Songnian Zhou. Later
work was done by Ralph Campbell and Kevin Dunlap, and others that contributed
include Jim Bloom, Smoot
and Mike Schwartz. Application maintenance was done by
Mike Karels and O. Kure.
Versions 4.9 and 4.9.1 of BIND were released by then the number two computer
company, Digital Equipment Corporation. The lead developer was
with assistance from Paul Albitz, Phil Almquist,
Fuat Baran, Alan
Bryan Beecher, Andy Cherenson,
Robert Elz, Art Harkin, Anant Kumar, Don Lewis,
Berthold Paffrath, Andrew Partan, Win
Treese, and Christophe Wolfhugel. After Vixie left to establish Vixie
Enterprises, he sponsored the development of BIND Version
4.9.2, and became the application's principal
Versions 4.9.3 on have been developed and maintained by the Internet
A major architectural update called Version 8 was co-developed by Bob Halley
and Paul Vixie and released in May 1997. Another major architectural rewrite
called Version 9 with enhanced security support was developed and released
in the year 2000.