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Networking Working Group                                       W. LazearRequest for Comments: 1031                                         MITRE                                                           November 1987MILNET NAME DOMAIN TRANSITIONSTATUS 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 hostLazear                                                          [Page 1]

RFC 1031                MILNET DOMAIN TRANSITION           November 1987   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 hostLazear                                                          [Page 2]

RFC 1031                MILNET DOMAIN TRANSITION           November 1987      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 1DOCUMENTATION   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.Lazear                                                          [Page 3]

RFC 1031                MILNET DOMAIN TRANSITION           November 1987     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 2RFC-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.Lazear                                                          [Page 4]

RFC 1031                MILNET DOMAIN TRANSITION           November 1987RFC-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 byRFC-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.Lazear                                                          [Page 5]

RFC 1031                MILNET DOMAIN TRANSITION           November 1987IMPLEMENTATIONS   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 90292-66954BSD 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  94720Lazear                                                          [Page 6]

RFC 1031                MILNET DOMAIN TRANSITION           November 1987   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 94043MS-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  02142Lazear                                                          [Page 7]

RFC 1031                MILNET DOMAIN TRANSITION           November 1987Tops-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 02139Symbolics 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 02142Xerox 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  94304Harris 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  53705-2280Lazear                                                          [Page 8]

RFC 1031                MILNET DOMAIN TRANSITION           November 1987Fuzzball 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 19716Multics 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, 85066-8000VAX/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.  15213Lazear                                                          [Page 9]

RFC 1031                MILNET DOMAIN TRANSITION           November 1987Macintosh 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 48105ORDERING 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) 859-3695Lazear                                                         [Page 10]