INTERNET-DRAFT                          Example, Test, & Fictitious TLDs
                                                              March 1998
                                                  Expires September 1998

           Example, Test, and Fictitious Top Level DNS Names
           -------- ----- --- ---------- --- ----- --- -----

                         Donald E. Eastlake 3rd
                            Aliza R. Panitz

                        Status of This Document

   This draft, file name draft-ietf-dnsind-test-tlds-08.txt, is intended to
   be become a Best Current Practice RFC.  Distribution of this document
   is unlimited. Comments should be sent to the DNS mailing list
   <> or to the authors.

   This document is an Internet-Draft.  Internet-Drafts are working
   documents of the Internet Engineering Task Force (IETF), its areas,
   and its working groups.  Note that other groups may also distribute
   working documents as Internet-Drafts.

   Internet-Drafts are draft documents valid for a maximum of six
   months.  Internet-Drafts may be updated, replaced, or obsoleted by
   other documents at any time.  It is not appropriate to use Internet-
   Drafts as reference material or to cite them other than as a
   ``working draft'' or ``work in progress.''

   To learn the current status of any Internet-Draft, please check the
   1id-abstracts.txt listing contained in the Internet-Drafts Shadow
   Directories on (East USA), (West USA), (North Europe), (South Europe), (Pacific Rim), or (Africa).

   [Changes in this draft from the last version resulted from discussion
   with IANA.]

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   To reduce the likelihood of conflict and confusion, a number of top
   level domain names are reserved for use in creating names for
   fictional purposes, private testing, as examples in documentation,
   and the like.  In addition, a few second level domain names reserved
   for use as examples are documented.

Table of Contents

      Status of This Document....................................1

      Table of Contents..........................................2

      1. Introduction............................................3
      2. TLDs for Fictional, Testing, & Documentation Examples...3

      3. Reserved Example Second Level Domain Names..............6
      4. Security Considerations.................................6

      Authors Addresses..........................................7
      Expiration and File Name...................................7

D. Eastlake, A. Panitz                                          [Page 2]


INTERNET-DRAFT                          Example, Test, & Fictitious TLDs

1. Introduction

   The global Internet Domain Name System is documented in [RFC 1034,
   1035, 1591] and numerous additional Requests for Comment.  It defines
   a tree of names starting with root, ".", immediately below which are
   top level domain names such as ".com" and ".us". Below top level
   domain names there are normally additional levels of names.

2. TLDs for Fictional, Testing, & Documentation Examples

   There is a need for top level domain (TLD) names that can be used for
   creating names which, without fear of conflicts with current or
   future actual TLD names in the global DNS, can be used for (1)
   realistic fictional names for literary or other purposes, (2) private
   testing of existing DNS related code, (3) examples in documentation,
   (4) DNS related experimentation, (5) invalid DNS names, or (6) other
   similar uses.

   For example, without guidance, a site might set up some local
   additional unused top level domains for testing of its local DNS code
   and configuration. Later, these TLDs might come into actual use on
   the global Internet.  As a result, local attempts to reference the
   real data in these zones could be thwarted by the local test
   versions. Or a work of fictional literature might be written with
   realistic fake domain names under a fake TLD, perhaps in URLs, which
   later caused confusion when that TLD came into actual use. Or test or
   example code might be written that accesses a TLD that is in use with
   the thought that the test code would only be run in restricted
   testbed net or the example never actually run.  Later, the test code
   could escape from the testbed or the example be actually coded and
   run on the Internet. Depending on the nature of the test or example,
   it might be best for it to be referencing a TLD permanently reserved
   for such purposes.

   To safely satisfy these needs, domain names are reserved as described
   below.  It is best to allocate a variety of names of different
   lengths now to reduce the probability of a need for further top level
   domain name creation and assignment for this purpose in the
   foreseeable future.

   The following eight top level domain names are reserved.

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        Note: two letter top level domain names are reserved for ISO
        3166 / Universal Postal Union two letter country codes.
        However, ISO 3166 reserves all two letter codes beginning with
        "x" for local use and states that they will never be assigned to
        a country.

   These names are available for special use in forming fictional names,
   in testing, as examples in documentation, etc. except for
   ".localhost" which is reserved for use as the local name of the
   loopback IP addresses (IPv4 and IPv6).

   ".invalid" is intended for use in online construction of domain names
   that are sure to be and are self labeled as invalid.  By appending
   ".invalid" to a domain name, you are sure of constructing a name that
   is not valid.  The ".localhost" TLD has traditionally been staticly
   defined in host DNS implementations as having an A record pointing to
   the loop back IP address and is reserved for such use.

   ".test" is particularly recommended for use in testing of current or
   new DNS related code..

   ".example" is particularly recommended for use in documentation or as

   It is recommended that fictional domain names be constructed using
   ".xy", ".xz", ".nil", and ".tld".

   [At the time of the issuance of this draft as an RFC, IANA will
   determine which, if any, of the above names will actually be entered
   into the IETF recommended root zone with a single TXT RR for each
   that will contain the string

        Reserved, see RFC nnnn.

   or such other information as IANA determines.  This text within
   square brackets will be modified to indicate which names are actually
   entered in root and what RR or RRs will be stored under them.

   Other data will not be stored under these names in the root zone
   except that the loopback A and AAAA [RFC 1886] resource records may
   be stored under ".localhost".  However, to assure proper operation of

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   hosts even when unable to access a root server, ".localhost" should
   still be locally staticly configured.

   [Note to RFC-Editor: replace nnnn above with the number of the RFC
   this draft gets issued as.]]

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3. Reserved Example Second Level Domain Names

   The Internet Assigned Numbers Authority (IANA) also currently has the
   following second level domain names reserved which can be used as

4. Security Considerations

   Confusion and conflict can be caused by the use of a current or
   future top level domain name as a fictitious name in literature, in
   experimentation or testing, as an example in documentation, or the
   like.  Test and experimental software can escape and end up being run
   against the global operational DNS.  Even examples used "only" in
   documentation can end up being coded and released or cause conflicts
   due to later real use and the possible acquisition of intellectual
   property rights in such "example" names.

   The reservation of several top level domain names for these purposes
   will minimize such confusion and conflict.

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   RFC 1034 - P. Mockapetris, "Domain names - concepts and facilities",

   RFC 1035 - P. Mockapetris, "Domain names - implementation and
   specification", 11/01/1987.

   RFC 1591 - J. Postel, "Domain Name System Structure and Delegation",

   RFC 1886 - S. Thomson, C. Huitema, "DNS Extensions to support IP
   version 6", December 1995.

Authors Addresses

   Donald E. Eastlake 3rd
   CyberCash, Inc.
   318 Acton Street
   Carlisle, MA 01741 USA

   Telephone:   +1 978 287 4877
                +1 703 620-4200 (main office, Reston, VA)
   FAX:         +1 978 371 7148

   Aliza R. Panitz
   AccessAbility Internet Services, Inc.
   12515 Greenbriar Road
   Potomac, MD 20854 USA

   Telephone: +1 301 983-3547
   FAX:       +1 301 983-4899

Expiration and File Name

   This draft expires September 1998.

   Its file name is draft-ietf-dnsind-test-tlds-08.txt.

D. Eastlake, A. Panitz                                          [Page 7]