rfc897.txt

RFC 相关的技术文档

RFC 897                                                    February 1984
Domain Implementation Schedule


   Interface to the World

      The interchange of mail with "other-systems" will have to continue
      pretty much as it does now (except that RELAY-HOST will become
      RELAY-HOST.ARPA) until organization names can be used.  Then
      representative organizations can be designated for each
      "other-system" in the domain server data bases that will then
      indirectly specify a mail-relay host.

Policy Statement

   The names of hosts will be changed to domain style names.  Hosts will
   begin to use domain style names on 14-Mar-84 and the use of old style
   names will be completely phased out before 2-May-84.

   This applies to both the ARPA research hosts and the DDN operational
   hosts.

Implication

   All Hosts Change Names

      The impact of introducing the domain style names is that all hosts
      change their names at least once.  Hosts that move to new domains
      or subdomains may change their names several times.

      Hosts have an official (or primary) name and possibly several
      nicknames.  When mail is sent from a host, the official name is
      used in the mail header address fields.

      Suppose, that in the old days before domains were thought of, a
      host changed its name.  What is the impact on users of changing
      the name of a host?  Suppose one host changed its name from FOO to
      BAR.

         Mail

            Mail that was sent before the name was changed can not be
            answered using mail program commands that automatically fill
            in the return address.  While it may be possible to use
            special tricks to fix up the "From" or the "To" users
            addresses, the "Cc" addresses are very difficult to correct.

            Mail that was sent to JOE@ABC from FRED@FOO can not be
            answered unless the change of name is known to the user or
            the mail program an ABC and the host name BAR substituted
            for FOO.


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RFC 897                                                    February 1984
Domain Implementation Schedule


            Mail that is sent to JOE@ABC from SAM@DEF with a cc to
            FRED@FOO can not be answered easily.

         Mailing Lists

            Any mailing lists that have mailboxes on the host that
            changed names will now have incorrect entries.

      The point is that while the host that changed names may be able to
      use special tricks for a while to fix things up for the users, it
      is difficult for other hosts to do this.

      A general trick is to make the old name a nickname for the host
      for some period of time.

      The introduction of domain style names means that all hosts change
      their names essentially at the same time.

         For example, USC-ISIF changes to USC-ISIF.ARPA

      To lessen the resulting havoc, the initial set of new names has a
      fixed relationship to the old names.  The first set of domain
      style names is exactly the old names with the domain name "ARPA"
      appended.  That is, if a hosts old name was "HOST-NAME", then its
      new name is "HOST-NAME.ARPA".

      To further lessen the havoc, there will be a period of time when
      both the old and the new names are allowed.  That is, the old
      names will be nicknames for a while.

   Primary Names

      In to old style names, host have an official or primary names and
      may have several nicknames.  For example,

         Primary Name             Nicknames

         USC-ISIF                 ISIF

         ADA-VAX                  ISI-VAXB  AJPO  VAXB

      In any case, the data base in such than given any of the names for
      a host one can find the address, and given the address one can
      find the primary name.

      In the new domain style name system this property must be
      maintained.  That is, given the Internet address of a host one


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RFC 897                                                    February 1984
Domain Implementation Schedule


      must be able to find the primary name of that host.  This calls
      for careful management of the distributed database by those in
      charge of the domains and subdomains.

The Time Table

   -- Nov 83  Plan and Schedule

      At this point the overall plan for the implementation of domain
      style names and name servers, and a schedule of events was
      published (RFC-881).  Also the draft design and specification for
      the protocol and data base were published (RFC-882, RFC-883).

   -- Nov 83  Initial Domain Style Host Name Table

      At this point a version of the host table which includes the
      domain style names is made available (DHOSTS.TXT).

   -- Feb 84  Domain Requirements Specification

      At this point the requirements for establishing a new domain are
      published as an RFC.

   14 Mar 84  Begin using Domain Style Names

      At this point all hosts should start using their domain style
      names as their official and primary names.  The standard table of
      host names contains domain style names as the official and primary
      name (DHOSTS.TXT becomes HOSTS.TXT).

   04 Apr 84  Server for ARPA Domain

      At this point several domain name servers are in operation to
      supply host name to internet address translations, one of these
      servers is at the NIC.

   04 Apr 84  Domain Table

      At this point a master table of top level domain names and their
      associated servers is established at the NIC.

   02 May 84  Stop using old style Names

      At this point the use of old style names must be completely phased
      out.




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RFC 897                                                    February 1984
Domain Implementation Schedule


   02 May 84  Certain New Domains

      At this point a few new domains may be established, in particular
      the DDN domain.

   06 Jun 84  General & Multilevel Domains

      At this point additional new domains may be established, if they
      meet the requirements.  Domain style names may have more than two
      segments.

   18 Jul 84  Organizational Domains

      Domain style names may identify organizations.  Finding an address
      for a host may involve a level of indirection.

   05 Sep 84  Decommission Host Table

      At this point the master host table maintained by the NIC need no
      longer be complete for the ARPA research community.  A full table
      of the DDN operational hosts will be maintained by the NIC.

   03 Oct 84  DDN Plan for Domains Name Service

      At this point the DDN PMO will establish a plan for the future
      support of name to address translations in the DDN community.

References

   [1]  Postel, J., "The Domain Names Plan and Schedule", RFC-881, USC
        Information Sciences Institute, November 1983.

   [2]  Mockapetris, P., "Domain Names - Concepts and Facilities",
        RFC-882, USC Information Sciences Institute, November 1983.

   [3]  Mockapetris, P., "Domain Names - Implementation and
        Specification", RFC-883, USC Information Sciences Institute,
        November 1983.











Postel                                                          [Page 8]