RFC 1031 UNKNOWN DNS · NAMING · TRANSITION

MILNET Domain Transition: MILNET name domain transition

The 1987 plan for moving the MILNET community from host tables to domain names.

On rfc-editor.org ↗
PUBLISHED
November 1987
AUTHORS
W.D. Lazear
STREAM
Legacy
MANDATORY CONVERSION DEADLINE
October 1989
HOST TABLE DISCONTINUED
October 1989
POLICY ANNOUNCED
October 1987, in a DDN Management Bulletin
ROOT SERVER OPERATIONAL TESTING
December 1986 to July 1987
CONVERSION STAGES
3
DOCUMENTS DESCRIBING THE SYSTEM
11 RFCs
DOI
10.17487/RFC1031

RFC text

Contents
Original text · RFC Editor View on rfc-editor.org ↗
Networking Working Group                                       W. Lazear
Request for Comments: 1031                                         MITRE
                                                           November 1987


                     MILNET NAME DOMAIN TRANSITION


STATUS OF THIS MEMO

   This RFC consolidates information necessary for the implementation of
   domain style names throughout the DDN/MILNET Internet community.
   Although no official policy has been published, the introduction of
   domain style names will impact all hosts in the DDN/MILNET Internet.
   The RFC is designed as an aid to implementors and administrators by
   providing 1) an overview of the transition process from host tables
   to domains, 2) a potential timetable for the transition, and 3)
   references to documentation and software relating to the DDN/ARPANET
   domain system.  Distribution of this RFC is unlimited.

BACKGROUND

   All MILNET hosts are expected to have a way of translating the name
   of any other host into its Internet address.  Although the current
   method of name resolution is to look up the information in a table of
   all hosts, this method of operation is cumbersome and relies on a
   central point of information.  The Network Information Center (NIC)
   maintains a table of hosts registered in the MILNET Internet and
   their addresses.  The size of this table and the frequency of updates
   has reached the limits of manageability.  The central host table is
   FTP'd by a host on a timely basis from the NIC, processed locally (to
   pare or reformat the table), and used in name resolution.

   The domain system uses a distributed database and software to perform
   the same functions as the host table.  In this system, host resolvers
   query domain servers for name resolution.  They may cache answers for
   performance improvement.  The domain servers each maintain a portion
   of the hierarchical database under separate administrative authority
   and control.  Redundancy is obtained by transferring data between
   cooperating servers.

   The domain system has been operating successfully on the ARPANET for
   over a year.  One indication of success is that the NIC's central
   host table is no longer a complete list (i.e., ARPANET does not
   depend primarily on the host table).  The domain system is being
   implemented on the MILNET with DoD military standard protocols.  The
   first step in changing to the domain system has been taken, as
   required by DDN Management Bulletin #32 (22 Jan 1987).  All host
   names were converted from a simple, flat namespace to a structured
   name consistent with domains.  In the second step, servers acting as
   the root of the database hierarchy were put in place.  In the next
   step, hosts are moving away from host table usage.

MIGRATION PATH

   All hosts will not change from host table to domain server usage at
   one time.  Accordingly, three stages of conversion to the domain
   system are envisaged.  These stages roughly correspond to 1)
   continuing to use the host table for all applications, 2) using the
   domain system for only some applications, and 3) using the domain
   system for all applications.  These stages will exist simultaneously
   as various hosts convert their application software according to
   available resources.  The following paragraphs discuss these stages
   in more detail.

   Host Table Only

      In the first stage, a host depends entirely on the host table for
      name resolution.  The table is obtained from the NIC's central
      copy and the resolution is done by local table scanning.  Most
      hosts are in this stage.

      Certain hosts may find it infeasible ever to convert to the domain
      system, owing to older architectures, unchangeable software, or
      other considerations.  At the end of the conversion period, the
      NIC will stop maintaining an internet host table.  To continue
      operations, hosts that do not convert will need to obtain an
      equivalent of the host table from some source.  This source may be
      another host with which a bilateral agreement has been negotiated
      offline, a community-of-interest host acting as central repository
      for that community, or a locally-maintained table of host names
      and addresses.  Transfer of the table from the source is a matter
      of local implementation and bilateral agreements.

   Domain System and Host Table

      In the second stage, a host will use both the host table and the
      domain system.  A likely scenario is that applications like TELNET
      and FTP will use the domain system and that MAIL will continue to
      use the host table for name resolution.  An alternate scenario is
      that batchstyle applications like MAIL would use the domain system
      and that the interactive applications would convert later.

      This stage is viewed as transitory, as hosts convert over to use
      the domain system exclusively.  It is highlighted as a separate
      stage to emphasize the need during transition for both the host
      table and the domain system.

   Domain System Only

      In the third and final stage, a host will have completed
      conversion and will be using the domain system exclusively.  This
      includes correct processing of the mailbox and mail exchanger
      resource records.

MIGRATION TIMETABLE

   Table 1 shows the events and dates involved in the MILNET transition
   from host table to domain system.  The operational testing of the
   root server software has been completed.  Voluntary conversion can
   begin immediately, with mandatory conversion required by October
   1989.  After this date, hosts not converted need to obtain the host
   table equivalent by private arrangement (see "Migration Path" above).

                                                      Start     End
        Milestone                                      Date     Date
        ===========================================   ======   ======
        Root server operational testing               Dec 86   Jul 87
        Policy announced in DDN Management Bulletin   Oct 87
        Host conversion                               Oct 87   Oct 89
        Host table discontinued                       Oct 89

                       MILNET Name Domain Timetable

                                  Table 1

DOCUMENTATION

   The Name Domain system is described in several documents that are
   maintained and available from the NIC in both online and in hardcopy
   form.  The documents are in "Request For Comments" format (RFC)
   commonly used in the Internet to document and discuss various
   networking issues.  The documents noted in Table 2 fully describe the
   concepts, conventions, enhancements, requirements, and operation of
   the Name Domain system.  The following paragraphs give a brief
   synopsis of each document.

     RFC    PH   DOCUMENT TITLE
     ===    ==   =======================================================

      799   *    Internet Name Domains
      819        Domain Naming Convention for Internet User Applications
      920        Domain Requirements
      921        Domain Name System Implementation Schedule - Revised
      952   *    Internet Host Table Specification
      953   *    Hostnames Server
      974        Mail Routing and the Domain System
     1032        Domain Administrators Guide
     1033        Domain Administration Operations Guide
     1034        Domain Names - Concepts and Facilities
     1035        Domain Names - Implementation Specification

   *  Included in the DDN Protocol Handbook

                           Name Domain Documents

                                  Table 2

   RFC-799

      This RFC is an early description of the concepts of a name domain
      system. It is exploratory in nature and offers scenarios for name
      resolution and mail forwarding.

   RFC-819

      This RFC is a think peice about hierarchical naming conventions
      for internetworking applications.  The conventions proposed are
      aligned along administrative rather than topological boundaries
      and is designed for interoperation among heterogeneous naming
      environments.  Further topics of discussion include mail relaying,
      name service approaches, and naming authorities.

   RFC-920

      This RFC contains a policy statement on the requirements of
      establishing a new domain in the ARPA Internet and introduces the
      limited set of top level domains.

   RFC-921

      This RFC contains a policy statement on the implementation
      schedule of the ARPA Internet domain system (as of October 1984).
      The discussion describes schedule and future operational
      scenarios, as well as the transition between the two.

   RFC-952

      This RFC specifies the format of the host/address table maintained
      by the NIC.

   RFC-953

      This RFC contains the official specification of the Hostname
      Server Protocol.  This TCP-based protocol accesses machine-
      readable name/address information in the format described by RFC-
      952 and is used by hosts to obtain all or a portion of the
      centralized host table.

   RFC-974

      This RFC presents a description of how mail systems are expected
      to route messages based on domain system information.  In
      particular, it discusses how mailers should interpret mail
      exchanger resource records for message routing to both host and
      domain names.

   RFC-1032

      This RFC describes the guidelines for a domain administrator to
      follow to establish a new domain.

   RFC-1033

      This RFC provides procedures for domain administrators in
      operating a domain server and maintaining their portion of the
      hierarchical database.

   RFC-1034

      This RFC introduces domain style names, their use for ARPA
      Internet mail and host address support, and the protocols and
      servers used to implement domains.  The concepts and facilities of
      the domain system are described.  The RFC also discusses the
      hierarchical database model, resource record usage, query
      formation, query resolution, and domain control.

   RFC-1035

      This RFC specifies the format of domain system transactions,
      discusses the implementation of domain servers, and explores the
      use of domain names in the context of mail and other network
      software.

IMPLEMENTATIONS

   Several implementations of the domain system exist.  The first two
   paragraphs (JEEVES and BIND) discuss the prominent (and most mature)
   two implementations and their authors/maintainers.  These
   implementations are available online.  The last paragraphs list
   implementations under development.  Points of contact can supply more
   information.

   The intent of listing these implementations is to give vendors the
   opportunity to inspect working code.  These implementations embody
   experience with the domain system and offer interpretations of the
   protocols found acceptable in operational environments.

Tops-20 Server and Resolver (JEEVES)

   Some domain root servers on the ARPANET are hosted on TOPS-20 systems
   and run the code called JEEVES.  The JEEVES resolver is specific to
   version 5 of TOPS-20.  The code is maintained by Paul Mockapetris
   (ISI), is available using anonymous FTP from host a.isi.edu, and
   resides in the files

                   <domain.version5>version5.mss
                   <domain.version5>version5.doc
                   <domain.version5>version5.txt

   His mail addresses are:

             ARPANET:  pvm@venera.isi.edu

             US MAIL:  USC Information Sciences Institute
                       4676 Admiralty Way
                       Marina del Rey, California 90292-6695

4BSD Unix Resolver and Server (BIND)

   Most hosts running lower level domain servers on the ARPANET are
   hosted on 4BSD systems and run the code called BIND.  This code is
   maintained for periodic releases by Mike Karels (UCB).  His mail
   addresses are:

             ARPANET:  karels@okeeffe.berkeley.edu

             US MAIL:  Computer Systems Research Group
                       Computer Science Division
                       Department of EE & CS
                       University of California
                       Berkeley, CA  94720

   There are two distribution mailing lists that publish information
   about BIND.  General discussions can be received by contacting
   bindrequest@ucbarpa.berkeley.edu and requesting to join the BIND
   list.  Information relating to testing developmental versions of BIND
   can be received by contacting bind-test-request@ucbarpa.berkeley.edu
   and requesting to join the BIND-TEST list.

   A commercial version of BIND is distributed with Sun Microsystems'
   operating system version 3.2.  The point of contact is Bill Nowicki.
   His addresses are:

             ARPANET:  nowicki@sun.com

             US MAIL:  Sun Microsystems
                       2550 Garcia Avenue
                       Mountain View, CA 94043

MS-DOS Server and Resolver

   FTP Software is working on a port of BIND to their PC/TCP environment
   under MS/DOS (their PC/TCP package).  They already have a resolver
   that depends on recursive queries.  The point of contact is Philip A.
   Prindeville.  His mail addresses are:

             ARPANET:  pap4@ai.ai.mit.edu

             US MAIL:  FTP Software Inc
                       P.O. Box 150
                       Kendall Sq. Branch
                       Boston, MA  02142

Tops-20 Resolver

   A resolver is being written in C for Tops-20 and ITS by Rob Austein.
   He encourages contacts from Tops-10, WAITS, and TENEX system
   programmers.  His mail addresses are:

             ARPANET:  sra@xx.lcs.mit.edu.

             US MAIL:  MIT LCS NE43-503
                       545 Technology Square
                       Cambridge MA 02139

Symbolics Resolver

   Symbolics Inc. has an implementation for the 36xx series Lisp
   Machines.  Steven L. Sneddon is the point of contact.  His addresses
   are:

             ARPANET:  sned@pegasus.scrc.symbolics.com

             US MAIL:  Manager, Networks and Communications
                       Symbolics, Inc.
                       11 Cambridge Center
                       Cambridge, MA 02142

Xerox Cedar Resolver

   Xerox has a resolver running in the Cedar language/environment at
   Xerox PARC.  John Larson is the point of contact.  His addresses are:

             ARPANET:  jlarson.pa@xerox.com

             US MAIL:  Xerox Palo Alto Research Center
                       3333 Coyote Hill Road
                       Palo Alto, CA  94304

Harris Resolver

   There is a domain resolver for the Harris H series that handles
   canonical name, host address, name server, and mail agent (MX)
   records.  Bruce Orchard is the point of contact.  His addresses are:

             ARPANET:  orchard/bruc@scarecrow.waisman.wisc.edu

             US MAIL:  549 Waisman Center
                       University of Wisconsin-Madison
                       1500 Highland Avenue
                       Madison, Wisconsin  53705-2280

Fuzzball Server and Resolver

   Dave Mills has both server and solver for the so-called PDP11/LSI- 11
   Fuzzballs.  However, these are not complete implementations and do
   not support zone transfers and so forth.  They have little use
   outside the fuzzball community, since the code is in assembler and is
   not for Unix.  His addresses are:

             ARPANET:  mills@udel.edu

             US MAIL:  Electrical Engineering Department
                       University of Delaware
                       Newark, DE 19716

Multics Resolver

   There is a resolver for Multics that is nearly ready for release.
   Art Beattie is the point of contact.  His addresses are:

             ARPANET:  beattie%pco@bco-multics.arpa

             US MAIL:  MS K55
                       Honeywell Bull
                       PO Box 8000
                       Phoenix, AZ, 85066-8000

VAX/VMS Resolver

   There is a partial resolver implementation (only supports address
   queries and IN-ADDR PTR lookups) that is part of the CMU/TEK TCP/IP
   package for VAX/VMS.  It is written in BLISS-32.  Vince Fuller is the
   point of contact.  His addresses are:

             ARPANET:  vince.fuller@c.cs.cmu.edu

             US MAIL:  Computer Science Department
                       Carnegie-Mellon University
                       Schenley Park
                       Pittsburgh, Pa.  15213

Macintosh Resolver and Server

   Tom Unger has ported BIND to the Macintosh.  This was done using the
   Macintosh Programmer's Workshop and CITI's MacIP that currently
   consists of IP, UDP, and a Berkeley style socket library.  His mail
   addresses are:

             ARPANET:  tom@citi.umich.edu

             US MAIL:  Center for Information and Technology Integration
                       University of Michigan
                       2901 Hubbard
                       Ann Arbor, MI 48105

ORDERING INFORMATION

   Documents are available online from the NIC (IP address 10.0.0.51 or
   26.0.0.73) by using FTP with the login ANONYMOUS and the password
   GUEST.  RFCs are in files named RFC:RFCnnn.TXT and are simple ASCII
   files ready for printing.  Pages within the documents are separated
   by a form feed character on a line by itself.

   Hardcopy of the documents and software mentioned in the discussions
   above may be obtained from the NIC or the author.  Prices are
   available on request and are documented in DDN Newsletter #50 (12 Dec
   1986).  The address and phone numbers of the NIC are listed below.

                        DDN Network Information Center
                        SRI International, Room EJ291
                        333 Ravenswood Avenue
                        Menlo Park, CA 94025

                        (800) 235-3155
                        (415) 859-3695

ISO Plain Language

On this page
PROBLEMMILNET machines found each other's addresses by looking up a single table of every host in the network, copied from a central registry. The table had grown to the point where it could no longer be managed, and every host on the network would be affected by the move to domain names.
MECHANISMThe RFC explains the domain system as a distributed database with its own hierarchy of servers, and lays out a three-stage path for hosts to move over, with a timetable running from late 1986 to October 1989.
WHY IT MATTEREDHosts that could not convert were told where to get an equivalent of the host table once the central one was withdrawn. The document also lists the RFCs describing the system and the implementations available at the time.

§1What This Document Is For

The RFC consolidates the information needed to implement domain style names throughout the DDN/MILNET Internet community. Although no official policy has been published, the introduction of domain style names will affect all hosts in the DDN/MILNET Internet, so the document is written as an aid to implementors and administrators.

It provides three things: an overview of the transition process from host tables to domains, a potential timetable for the transition, and references to documentation and software relating to the DDN/ARPANET domain system.

This is a briefing for the people who have to make the change: what is happening, when it has to happen, and where to find the specification and the code.

§2Host Tables and the Domain System

All MILNET hosts are expected to have a way of translating the name of any other host into its Internet address. The current method of name resolution is to look the information up in a table of all hosts, which is cumbersome and relies on a central point of information. The Network Information Center maintains the table of hosts registered in the MILNET Internet and their addresses, and the size of that table and the frequency of updates had reached the limits of manageability. The central host table is fetched by a host on a timely basis from the NIC, processed locally to pare or reformat the table, and used in name resolution.

The domain system uses a distributed database and software to perform the same functions as the host table. In this system, host resolvers query domain servers for name resolution and may cache answers for performance. The domain servers each maintain a portion of the hierarchical database under separate administrative authority and control, and redundancy is obtained by transferring data between cooperating servers.

The domain system had been operating successfully on the ARPANET for over a year. One indication of that success was that the NIC's central host table was no longer a complete list: the ARPANET no longer depended primarily on the host table. The domain system was being implemented on the MILNET with DoD military standard protocols, and the first step of the change had already been taken as required by DDN Management Bulletin number 32 of 22 January 1987: all host names were converted from a simple, flat namespace to a structured name consistent with domains. In the second step, servers acting as the root of the database hierarchy were put in place, and in the next step hosts were to move away from host table usage.

The old way was one big list, kept in one place and copied to everybody. The new way is a hierarchy: each server holds the part of the naming tree it is responsible for, and a machine asks a server rather than reading a file. The ARPANET had been running this way for a year by the time this RFC was written.

§3Three Stages of Conversion

Not all hosts will change from host table to domain server usage at one time, so three stages of conversion are envisaged. They roughly correspond to continuing to use the host table for all applications, using the domain system for only some applications, and using the domain system for all applications. The stages exist simultaneously as various hosts convert their application software according to available resources.

In the first stage, host table only, a host depends entirely on the host table for name resolution. The table is obtained from the NIC's central copy and the resolution is done by local table scanning. Most hosts are in this stage. Certain hosts may find it infeasible ever to convert, owing to older architectures, unchangeable software or other considerations, and at the end of the conversion period the NIC will stop maintaining an internet host table. To continue operations, hosts that do not convert will need to obtain an equivalent of the host table from some source: another host with which a bilateral agreement has been negotiated offline, a community-of-interest host acting as central repository for that community, or a locally-maintained table of host names and addresses. Transfer of the table from the source is a matter of local implementation and bilateral agreements.

In the second stage, domain system and host table, a host uses both. A likely scenario is that applications such as TELNET and FTP use the domain system while MAIL continues to use the host table for name resolution; an alternate scenario is that batch-style applications such as MAIL use the domain system and the interactive applications convert later. This stage is viewed as transitory, as hosts convert over to using the domain system exclusively, and it is highlighted as a separate stage to emphasize the need during the transition for both the host table and the domain system.

In the third and final stage, domain system only, a host has completed conversion and uses the domain system exclusively, including correct processing of the mailbox and mail exchanger resource records.

Hosts move over one application at a time. First everything still uses the old list; then some applications use the new system and others still use the list; eventually everything uses the new system. A machine that is too old to change will have to find its own copy of the list, because the central one is going away.

THE THREE STAGES OF THE CONVERSION
StageWhat the host usesNotes
Host table onlyThe central list, copied from the NIC and scanned locally.Most hosts were in this stage.
Domain system and host tableBoth, for different applications.Viewed as transitory. TELNET and FTP might move first, or MAIL might.
Domain system onlyThe domain system alone.Includes correct processing of mailbox and mail exchanger records.

§4The Timetable

The table of milestones for the MILNET transition from host table to domain system sets four events with their dates. The operational testing of the root server software ran from December 1986 to July 1987. The policy was announced in a DDN Management Bulletin in October 1987. Host conversion ran from October 1987 to October 1989. The host table was discontinued in October 1989.

The operational testing of the root server software has been completed, voluntary conversion can begin immediately, and mandatory conversion is required by October 1989. After that date, hosts that have not converted need to obtain the host table equivalent by private arrangement, as described in the migration path above.

The servers were tested over the second half of 1986 and the first half of 1987. The policy was announced in the autumn of 1987, and the two years after that were for hosts to convert. When the period ended in October 1989, the central list was withdrawn.

THE MILNET TRANSITION TIMETABLE
  1. 1986Root server operational testing begins in December
  2. 1987Root server operational testing ends in July; the policy is announced in a DDN Management Bulletin in October
  3. 1989Mandatory conversion and discontinuation of the host table, both in October

§6Where to Get the Documents

The documents are available online from the NIC, at IP address 10.0.0.51 or 26.0.0.73, by using FTP with the login ANONYMOUS and the password GUEST. The RFCs are in files named RFC:RFCnnn.TXT and are simple ASCII files ready for printing, with pages separated by a form feed character on a line by itself.

Hardcopy of the documents and of the software mentioned in the discussions above may be obtained from the NIC or from the author. Prices are available on request and are documented in DDN Newsletter number 50 of 12 December 1986.

Everything was published in the ordinary way: fetch the files by anonymous FTP from the NIC, or order paper copies. The machine-readable copies were plain text with form feeds between pages, ready to print.

§7References