Skip to main content

Domain Names and Company Name Retrieval

The information below is for an old version of the document that is already published as an RFC.
Document Type
This is an older version of an Internet-Draft that was ultimately published as RFC 2345.
Author Dr. John C. Klensin
Last updated 2013-03-02 (Latest revision 1998-03-17)
RFC stream Legacy stream
Stream Legacy state (None)
Consensus boilerplate Unknown
RFC Editor Note (None)
IESG IESG state RFC 2345 (Experimental)
Telechat date (None)
Responsible AD (None)
Send notices to (None)
Network Working Group                                        J Klensin
Internet Draft                                                     MCI
Document: draft-klensin-tld-whois-02.txt                   T Wolf, Jr.
                                                      Dun & Bradstreet
                                                         July 29, 1997

               Domain Names and Company Name Retrieval

Status of this Memo

   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,,, or

   A revised version of this draft document may be submitted to the
   RFC Editor for processing as an Experimental RFC for the Internet
   Community.  Discussion and suggestions for improvement are
   requested. This draft will expire before January 30, 1998.
   Distribution of this draft is unlimited. 

   Changes from prior draft: Small technical clarifications.


   Location of web information for particular companies based on
   their names has become an increasingly difficult problem and the
   Internet and the web grow.   The use of a naming convention and
   the domain name system (DNS) for that purpose has caused
   complications for the latter while not solving the problem.
   While there have been several proposals to use contemporary,
   high-capability, directory service and search protocols to reduce
   the dependencies on DNS conventions, none of them have been
   significantly deployed.

   This document proposes a company name to URL mapping service based
   on the oldest and least complex of Internet directory protocols,
   whois, in order to explore whether and extremely simple and
   widely-deployed protocol can succeed where more complex and
   powerful options have failed or been excessively delayed.

1. Introduction and Context

   In recent months, there have been many discussions in various
   segments of the Internet community about "the top level domain
   problem".  Perhaps characteristically, that term is used by
   different groups to identify different, and perhaps nearly
   orthogonal, issues.  Those issues include:

   1.1.  A "domain administration policy" issue.

   1.2.  A "name ownership" issue, of which the trademark issue may
         constitute a special case.

   1.3.  An information location issue, specifically the problem of
         locating the appropriate domain, or information tied to a
             domain, for an entity given the name by which that entity is
                 usually known.

   Of these, controversies about the first two may be inevitable
   consequences of the growth of the Internet.  There have been
   intermittent difficulties with top level domain adminstration and
   various attempts to use the domain registry function as a
   mechanism for control of service providers or services from time
   to time since a large number of such domains started being
   allocated.  Those problems led to the publication of the policy
   guidelines of [RFC1591].

   The third appears to be largely a consequence of the explosive
   growth of the World Wide Web and, in particular, the exposure of
   URL formats [URL] to the end user because no other mechanisms have
   been available.  The absence of an appropriate and adequately-
   deployed directory service has led to the assumption that it
   should be possible to locate the web pages for a company by use of
   a naming convention involving that company's name or product name,
   i.e., for the XYZ Company, a web page located at

   has been assumed.

   However, as the network grows and as increasing numbers of web
   sites are rooted in domains other than ".COM", this convention
   becomes difficult to sustain: there will be too many organizations
   or companies with legitimate claims --perhaps in different lines
   of business or jurisdictions-- to the same short descriptive
   names.  For that reason, there has been a general sense in the
   community for several years that the solution to this information
   location problem lies, not in changes to the domain name system,
   but in some type of directory service.

   But such directory services have not come into being.  There has
   been ongoing controversy about choices of protocols and accessing
   mechanisms.  IETF has published specifications for several
   different directory and search protocols, including [WHOIS++],
   [RWHOIS], [LDAP], [X500], [GOPHER].  One hypothesis about why this
   has not happened is that these mechanisms have been hard to select
   and deploy because they are much more complex than is necessary.
   This document proposes an extremely simple alternative.

2. Using WHOIS

   The WHOIS protocol is the oldest directory access protocol in use
   on the Internet, dating in published form to March 1982 and first
   implemented somewhat earlier.  The procotol itself is simple and
   minimalist: the client opens a telnet connection to the WHOIS
   port (43) and transmits a line over it.  The server looks up the
   line in a fashion that it defines, returns one or more lines of
   information to the client, and closes the connection.

   We suggest that modifications or add-ins be created to Web
   browsers that would access a new, commercially-provided Whois
   server, sending a putative company name and receiving back one or
   more lines, each containing a URL followed by one or more blanks
   and then a matching company name (that order was chosen to
   minimize parsing problems: since URLs cannot contain blanks, the
   first blank character marks the end of the URL and the next
   non-blank marks the beginning of the company name).  As is usual
   with Whois, the criteria used by the server to match the incoming
   string is at the server's discretion.  The difference between this
   and the protocol as documented in [WHOIS] is that exactly one
   company name is returned per line (see section 3 for details of

   The client would then be expected to:

   (i) If a single line (company name and URL) is returned, either
       ask for confirmation or simply fetch the associated URL as if
       it had been typed by the user.

   (ii) If multiple lines (names) are returned, present the user with
       a choice, presumably showing company names rather than (or
       supplemented by) URLs, then fetch using the URL selected.

   Obviously, while the most convenient use of the services
   contemplated in this document would occur through a client that
   was part of, or intimately connected with, a Web browser, a user
   without that type of facility could utilize a traditional WHOIS
   client and paste or otherwise transfer the relevant information
   into the target location of a browser.

3. Formats, versions, and international character sets

   Preliminary work with the approach suggested above suggests that
   some specific conventions about syntax and variations would be

3.1 Line sent from client to server.

   These lines may take either of two forms:

   (i) A simple 7-bit ASCII string, containing a "company name"

   (ii) A string in the format (using the ABNF notation of RFC 822):
       Variation "/" 1*Octet

           Variation :== "0" | ( Non-zero-digit 1*Digit)
           Non-zero-digit :== 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9
           Digit :== 0 | Non-zero-digit

       Where Octet is any eight-bit sequence, representing a prefixed
       variation number.

   The first form will be construed as equivalent to the second form
   with the leading string "0/".  Variation numbers are specified in
   section 3.3.

   In all cases, the interpretation of what "company name" might mean
   and, in particular, what variations of form or spelling,
   abbreviations, and so on, might be accepted is strictly up to the
   interpretation of the server.  If rules driving the server lead to
   the conclusion that a string matches some company in its data,
   the correctness or incorrectness of that decision is not covered
   by this specification.

   For variation 0 and, by default for all others, any alphabetic
   text in lines is to be construed in a case-insensitive fashion.

3.2 Lines sent from server to client.

   The server is expected to return one or more lines to the client,
   depending on its interpretation of the input string.  In general,
   each line will consist, as described above, of a URL, a space, and
   a "company name".  This document deliberately does not specify the
   content or semantics of the "company name" string.  It might be a
   name, or a name and descriptive information such as location and
   type of business, or other information at the option of the
   server.  The expectation, as mentioned above, is that the
   information will be displayed by the client to aid users in
   selecting the appropriate URL.

   These lines, consistent with normal Internet practice, will be
   terminated by a CR LF sequence (rather than one or the other of
   those control characters).

   When and if different variation numbers are introduced, their
   specifications may include variations on what the server is
   expected to return.

   In lieu of "URL and company name" responses, the Server may also
   return "error messages".  These take the form of lines containing:

         "///" SP String

    where the String is 7-bit ASCII with no control characters other
        than SP, unless the variation associated with the variation
        number specifies otherwise.  For this experiment, all "error
        messages" but the following two are discouraged:

          /// Not found
                    Indicating that the "company name" does not 
                    match anything
          /// Variation not supported
                    Indicating that the variation number supplied 
                    by the client is not recognized by the server.

3.3.  Registered variations

  The following two variations are established as part of this

  0/        Query and response are in 7-bit ASCII, no controls other
            than SP, "Company name" separated from URL by one or more
                        SP characters.

  1/        Query and response are in UTF-8, no controls other than
            SP, "Company name" separated from URL by one or more
                        SP characters, no specification of language on either
                        input or output.

   The authors will maintain a registry of additional variations
   which they hope will be very short (see section 9).  If this
   specification evolves into a proposed standard after an
   experimental period, the draft for that standard will propose that
   the registry be turned over to IANA. 

4. Alternatives not chosen

   Few comments on the initial draft of this document addressed the
   basic model or protocol design for the service discussed.
   Instead, they focused on inquiring about the decisions we didn't
   make and about beliefs about the protocol specification that were
   not intended by the authors.  The latter have been, we hope,
   corrected.  Questions of the following three types predominated in
   the first category. 

4.1.  Why didn't you use <insert-favorite-directory-protocol-here>?

   Many notes raised the question of how much more could be done with
   a higher-powered directory protocol rather than the extremely
   simple WHOIS.  Questions were raised about LDAP, X.500 DAP, CCSO,
   RWHOIS, and WHOIS++.  We had several reasons for avoiding them.
   The most important has been a strong commitment to see how much
   can be done with an extremely simplistic approach, and WHOIS
   represented the most simplistic approach we could find.  If it
   turns out to be too simple in practice, things can always evolve
   to one or more of the more advanced protocols.   But, if we
   started with one of them, we would never get that information.
   Other issues included:

   * None of the existing directory proposals has really emerged as
     the "right" solution with a large installed base.  The deployed
         base of WHOIS and WHOIS clients is huge, and using it avoids
         either having to make a premature choice of "winner" or to
         become embroiled in the debate.

   * For the casual user, the mechanisms needed to activate the
     extensive attribute-based directory searches of the stronger
         protocols are just too complicated and may actually act as a
         deterrent to effective use.

   * Substantially since the dawn of the ARPANET, the Internet
     experience has been that setting up a directory service is easy,
         but that maintaining one and keeping the records up-to-date is
         extremely difficult.  The economics of operating an effective
         directory service and keeping everything up to date may will
         require a revenue-producing product.  Use of a very simple
         protocol for the basic service creates a situation in which
         basic service can rationally be given away while more advanced
         service are operated on a charge or subscription basis.

4.2 And why not use a Web search engine?

   Web search engines are immensely effective and powerful, but
   address a different problem than this protocol.  The protocol
   model here does involve a directory lookup, using a presumed
   company name as a key.  The quality of the result will depend
   on the quality of the underlying directory and the editorial and
   research work that goes into its construction (neither of which
   are matters for the protocol itself -- we trust that marketplace
   pressures will separate good servers from poor ones).  Web search
   engines are often more effective at locating information about
   companies than the specific company-designated web pages.

4.3. Why not return a more highly structured information format
rather than a simple pair of URL and "company name"?

   Again, the goal was to keep things extremely simple and, in
   particular, permit minimal interpretation between the user's input
   and the query and between the response and a display or action.
   Some of the inquiries on this subject were due to
   misunderstandings about the implications of the "company name"
   field; the semantics of that field have been clarified above.  We
   also wanted to avoid the level of standardization implied by a
   tagging scheme: highly-structured fields might lead either to
   interoperability problems or excessive restriction on what might
   be returned.

5. Thoughts on Directory Providers

   There is no technical reason why there should be only one provider
   of company name to URL mapping services using this protocol, nor
   is there any reason for registries of such providers.  Presumably,
   servers that provide the best-quality mappings will eventually
   prevail in the marketplace.  However, as with most traditional
   uses of WHOIS, it is desirable for implementations of clients (or
   Web browsers supporting this protocol) to allow for user choice of
   servers through configuration options or the equivalent.

6. References

   [RFC1591]  J. Postel, "Domain Name System Structure and
       Delegation",  RFC 1591, March 3, 1994

   [GOPHER] F. Anklesaria, M. McCahill, P. Lindner, D. Johnson, D.
       John, D. Torrey, B. Alberti, "The Internet Gopher Protocol
           (a distributed document search and retrieval protocol)",
           RFC 1436, 03/18/1993.

   [LDAP]  W. Yeong, T. Howes, S. Kille, "Lightweight Directory
       Access Protocol", RFC 1777, 03/28/1995.

   [RWHOIS]   S. Williamson, M. Kosters, "Referral Whois Protocol
       (RWhois)", RFC 1714, 12/15/1994. 

   [URL]   T. Berners-Lee, L. Masinter, M. McCahill, "Uniform
       Resource Locators (URL)", RFC 1738, December 20, 1994.

   [WHOIS] E. Feinler, K. Harrenstien, M. Stahl, "NICNAME/WHOIS", 
       RFC 954, 0/01/1985. 

   [WHOIS++]  P. Deutsch, R. Schoultz, P. Faltstrom, C. Weider,
       "Architecture of the WHOIS++ service", RFC 1835, August 16,

   [X500]  R. Wright, A. Getchell, T. Howes, S. Sataluri, P. Yee, W.
       Yeong, "Recommendations for an X.500 Production Directory
           Service", RFC 1803, 06/07/1995.

   [Z39.50]  C. Lynch, "Using the Z39.50 Information Retrieval
       Protocol in the Internet Environment", RFC 1729, 12/16/1994. 

7. Security Considerations

   This suggested use of the WHOIS protocol adds no significant
   security risks to those of traditional applications of the
   protocol which is one of the most widely-deployed applications on
   the Internet.  As usual, servers should expect to use the string
   sent to them as an information retrieval key, not as a function to
   be executed in some way.  A more significant risk would arise if
   the server supporting the translation function were somehow
   spoofed; in that case, an incorrect URL might be returned for a
   particular company. As with the possibility of finding an
   incorrect page using naming conventions, the best protection
   against the risks that could then occur is careful attention to
   certificates, signatures, and other authenticity-indicating

8. Acknowledgements

   This memo was inspired by a many discussions over the last few
   years about the status and uses of the domain name system, 
   information location using conventions about domain names,
   exposure of URLs to end users, and convergence of directory and
   search protocols.  While the people involved are too numerous to
   attempt to list, the authors would like to acknowledge their
   contributions and comments.

   Martin Hamilton, Keith Moore, and Gary Oglesby made important
   suggestions that have contributed to the revision of this draft.

9. Authors' Address

 John C. Klensin
 MCI Internet Architecture
 800 Boylston St, 7th floor
 Boston, MA 02199
    Tel: +1 617 960 1011

 Ted Wolf, Jr.
 Electronic Commerce
 Dun & Bradstreet Information Services
 3 Sylvan Way
 Parsippany, NJ 07054
    Tel: +1 201 605 6308

 Address for purposes of registering variants only: