RFC 1401 (rfc1401) - Page 3 of 8

Correspondence between the IAB and DISA on the use of DNS

RFC 1401            IAB & DISA Correspondence on DNS        January 1993


Attachment

              The Domain Name System is an Internet Necessity

                         Internet Activities Board

                               February 1992

   Over the last several years, the Internet has evolved in size so
   extensively that it has become infeasible to provide directory
   services through a database maintained at a single, central
   repository.  Both the size and the dynamics of the required data make
   such an approach impractical.  Recognizing this problem several years
   ago [1], the Internet community has adopted the Domain Name System
   [2-5] as the principal means of achieving host name to IP address
   mappings.  During this time, almost the entire Internet has converted
   from the use of the static name-to-address mapping tables thus far
   centrally maintained at the DDN Network Information Center, to the
   use of the more dynamic, up-to-date address mapping provided by DNS
   mechanism.

   There are still large fractions of the Internet community which rely
   on the use of a centrally-maintained file ("hosts.txt") to accomplish
   this mapping function.  The MILNET community appears to have
   substantial pockets of dependence on table-driven mappings, for
   example.  Although a plan for achieving a MILNET transition to use of
   the Domain Name System was worked out in 1987, the transition is
   incomplete and, as a result, naming services (i.e., host name lookups
   on the MILNET) are many times still provided via static tables rather
   than the distributed, and far more accurate, Domain Name System.
   Ironically, most of the commercial, off-the-shelf software for TCP/IP
   supports the user of the Domain Name System, so a policy of uniform
   support and application of DNS would go a long way toward improving
   the Defense Department data communication infrastructure, insofar as
   it is dependent on TCP/IP to interconnect hosts on LANs and WANs.

   The use of different means for name-to-address mappings by different
   parties in the network community leads to unsynchronized and
   inconsistent databases, which inevitably result in reachability
   failures by users attempting to connect to network resources.
   Moreover, the special facilities of the Domain Name System, such as
   the MX (Mail eXchange) record, make it possible to include systems
   not directly on the Internet into the universe of addressable
   parties.  MX records also allow a network administrator to prioritize
   a list of alternative e-mail relays in case the final destination is
   not reachable.  Systems which do not support MX records, but rather
   still depend on the "hosts.txt" information, pose a serious obstacle
   to network connectivity, as well as to the operation and management



IAB