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Network Working Group J. Klensin Request for Comments: 2345 MCI Category: Experimental T. Wolf Dun & Bradstreet G. Oglesby MCI May 1998 Domain Names and Company Name Retrieval Status of this Memo This memo defines an Experimental Protocol for the Internet community. It does not specify an Internet standard of any kind. Discussion and suggestions for improvement are requested. Distribution of this memo is unlimited. Copyright Notice Copyright (C) The Internet Society (1998). All Rights Reserved. Abstract Location of web information for particular companies based on their names has become an increasingly difficult problem as 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 an 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: Klensin, et. al. Experimental [Page 1] RFC 2345 Domain Names and Company Name Retrieval May 1998 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 http://www.xyz.com/ or http://www.xyz-company.com/ 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], Klensin, et. al. Experimental [Page 2] RFC 2345 Domain Names and Company Name Retrieval May 1998 [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 syntax). 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. Klensin, et. al. Experimental [Page 3] RFC 2345 Domain Names and Company Name Retrieval May 1998 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 useful. 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 2234 [ABNF]): 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 Klensin, et. al. Experimental [Page 4] RFC 2345 Domain Names and Company Name Retrieval May 1998 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 specification: 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 IANA will maintain a registry of additional variations which it is hoped will be very short. Requests for additional variations should be sent via email to: iana@iana.org. Klensin, et. al. Experimental [Page 5] RFC 2345 Domain Names and Company Name Retrieval May 1998 4. Alternatives not chosen Few comments on the initial drafts 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. Klensin, et. al. Experimental [Page 6] RFC 2345 Domain Names and Company Name Retrieval May 1998 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. Demo Application To illustrate the proposed functionality of this document, a prototype of both the server and client have been made able for demonstration purposes. 6.1 Server The TLD-WHOIS demonstration server is available at "companies.mci.net". The server contains a database of approximately 209,000 company entries provided by Dun and Bradstreet. The server will generally respond back to a query within 15 seconds. If the server has the response cached from a previous query, the return time will be significantly shorter. Klensin, et. al. Experimental [Page 7] RFC 2345 Domain Names and Company Name Retrieval May 1998 If 10 or more entries are found in the database for the query, only the top 10 will be returned in the response. For the purposes of this demonstration, there is no provision for submitting additions or changes to the database. The authors and the sponsoring companies are not responsible for the accuracy of the data provided by this prototype. Our apologies if your company is not listed. 6.2 Client 6.2.1 Download Location: A demonstration client for the Windows 95/Nt platforms is available for public download through anonymous ftp at: ftp.mci.net/pub/ietf/company/demo.exe, or via the web: ftp://ftp.mci.net/pub/ietf/company/demo.exe File size is approximately 1.9 MB. 6.2.2 Setup Instructions: a) Download the client installation software from the site mentioned above to a local 32 bit Windows computer. The client installation software has been compressed using the self-extracting archive application from InstallShield The default name for the download is "demo.exe". b) Double click on the file through File Explorer or run the program through the START menu. c) Select "Setup" to allow InstallShield to uncompress the files needed to install the demonstration client to a temporary directory. InstallShield will then automatically launch the main application Setup program. d) The main setup program will install the demo application files and make the necessary additions to the Windows Registry. No user action is required. e) Upon completion of installation you will be prompted to run the application or to exit setup. Klensin, et. al. Experimental [Page 8] RFC 2345 Domain Names and Company Name Retrieval May 1998 6.2.3 Paranoia: What did you just do to my computer? Files Copied: companyname.exe Main program executable whois.ocx WhoIs module from Mabry Software led.ocx LED module from Mabry Software msvbvm50.dll Microsoft Visual Basic 5.0 runtime file stdole2.tlb Microsoft Visual Basic 5.0 runtime file oleaut32.dll Microsoft Visual Basic 5.0 runtime file olepro32.dll Microsoft Visual Basic 5.0 runtime file comcat.dll Microsoft Visual Basic 5.0 runtime file asyncfilt.dll Microsoft Visual Basic 5.0 runtime file crtl3d32.dll Installshield control used for installation only Registry Changes: Created key under HKEY_CLASSES_ROOT called Who This entry is used to enable the Microsoft Internet Explorer's pluggable protocol handler. The key contains several sub-entries that list the path and command to the companyname executable. The pluggable protocol hander provides the necessary hooks to launch the companyname application whenever the WHO:// URL is submitted in the address line of Internet Explorer. 6.2.4 Using the Program 6.2.4.1 Standalone Operation: From the Start Menu, select the Programs \ Companyname \ companyname. Alternatively, it can be launched from Start: Run c:\windows\companyname.exe Enter the name of the company that you are attempting to locate and press OK. A status box will be displayed while the client is communicating with the server until a response is returned. The possible returns are: a) Message box saying that, "Your request was not found." This means that the company information that was submitted was not found in the database. Klensin, et. al. Experimental [Page 9] RFC 2345 Domain Names and Company Name Retrieval May 1998 b) A list box containing 2 - 10 company names sorted high to low by score. Highlight one of the names and press the launch button. The program will launch the default web browser for your computer and navigate to the site. c) The default web browser launches and navigates to a site. This means that only one match was found in the database and that match is opened directly without user intervention. 6.2.4.2 Within Internet Explorer From the Address Line within the web browser, enter "WHO://" followed by the name of the company that you wish to search for and press the enter key. Note: Since the company name is entered within the URL space of the browser, it can not contain spaces. If you wish to send a search string that contains spaces, enter "WHO://" with no company information. The application will display the dialogue window as described in standalone mode for you to enter the search criteria. A status box will be displayed while the client is communicating with the server until a response is returned. The possible returns are: a) Message box saying that, "Your request was not found." This means that the company information that was submitted was not found in the database. b) A list box containing 2 - 10 company names sorted high to low by score. Highlight one of the names and press the launch button. The program will launch the default web browser for your computer and navigate to the site. c) The default web browser launches and navigates to a site. This means that only one match was found in the database and that match is opened directly without user intervention. 6.2.5 Client Customization The name of the Whois server is hardcoded within the application to "companies.mci.net". No initialization file or registry keys are needed for the default configuration. Realizing that some testers may have proxy servers on their corporate systems and that others may wish to test the client against a different Whois server, the client supports a mechanism for changing the default server. To enable the server customization, follow these steps: Klensin, et. al. Experimental [Page 10] RFC 2345 Domain Names and Company Name Retrieval May 1998 a) Create a new directory in the root of the C: Drive called "companyname" b) Using Notepad or any text editor create a new file called "whois.ini" c) Add a new line to the file beginning with "SERVER= <server name>". Do not include the double quotes around the tag. <server name> would be the IP Address or DNS name of the new Whois or proxy server. d) End the line with a carriage return. e) Save the file as a plain text file back to "c:\companyname\whois.ini" 6.2.6 Client Limitations: The demonstration software and database are provided "as is". No warranties are stated or implied. Use at your own risk. The demonstration client is supported only on 32 bit Intel Windows platforms. It has been tested on Windows 95, Windows NT 4.0 and Windows 98 beta RC0. Use of the WHO:// URL moniker from within the web browser is supported only under Microsoft Internet Explorer. TCP Port 43 must be cleared through firewalls for client to communicate with the server. Refer to the section on client customization if you need to utilize a proxy server to traverse a firewall. When using the Address Line entry method within Microsoft Internet Explorer, spaces are not permitted within the search string. 7. References [ABNF] Crocker, D., and P. Overell, Eds., "Augmented BNF for Syntax Specifications: ABNF", RFC 2234, November 1997. [RFC1591] Postel, J., "Domain Name System Structure and Delegation", RFC 1591, March 1994. [GOPHER] Anklesaria, F., McCahill, M., Lindner, P., Johnson, D., John, D., Torrey, D., and B. Alberti, "The Internet Gopher Protocol (a distributed document search and retrieval protocol)", RFC 1436, March 1993. Klensin, et. al. Experimental [Page 11] RFC 2345 Domain Names and Company Name Retrieval May 1998 [LDAP] Yeong, W., Howes, T., and S. Kille, "Lightweight Directory Access Protocol", RFC 1777, March 1995. [RWHOIS] Williamson, S., and M. Kosters, "Referral Whois Protocol (RWhois)", RFC 1714, December 1994. [URL] Berners-Lee, T., Masinter, L., and M. McCahill, "Uniform Resource Locators (URL)", RFC 1738, December 1994. [WHOIS] Feinler, E., Harrenstien, K., and M. Stahl, "NICNAME/WHOIS", RFC 954, October 1985. [WHOIS++] Deutsch, P., Schoultz, R., Faltstrom, P., and C. Weider, "Architecture of the WHOIS++ service", RFC 1835, August 1995. [X500] Wright, R., Getchell, A., Howes, T., Sataluri, S., Yee, P., and W. Yeong, "Recommendations for an X.500 Production Directory Service", RFC 1803, June 1995. [Z39.50] Lynch, C., "Using the Z39.50 Information Retrieval Protocol in the Internet Environment", RFC 1729, December 1994. 8. 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 information. 9. IANA Considerations As provided in section 3.3, above, this experiment requests that IANA maintain a registry of query variation forms and that the registry be initialized with the two values specified in that section. Klensin, et. al. Experimental [Page 12] RFC 2345 Domain Names and Company Name Retrieval May 1998 10. 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, Tom Thornbury and Ed Trembicki-Guy made important suggestions that have contributed to the revision of this memo. 11. Authors' Addresses John C. Klensin MCI Internet Architecture 800 Boylston St, 7th floor Boston, MA 02199 USA Phone: +1 617 960 1011 EMail: klensin@mci.net Ted Wolf, Jr. Electronic Commerce Dun & Bradstreet Information Services 3 Sylvan Way Parsippany, NJ 07054 USA Phone: +1 201 605 6308 EMail: ted@usa.net Gary W. Oglesby MCI Internet Architecture 842 N. Ahoy Dr. Gilbert, AZ 85234 USA Phone: +1 415 538 1100 EMail: gary@mci.net Klensin, et. al. Experimental [Page 13] RFC 2345 Domain Names and Company Name Retrieval May 1998 12. Full Copyright Statement Copyright (C) The Internet Society (1998). All Rights Reserved. This document and translations of it may be copied and furnished to others, and derivative works that comment on or otherwise explain it or assist in its implementation may be prepared, copied, published and distributed, in whole or in part, without restriction of any kind, provided that the above copyright notice and this paragraph are included on all such copies and derivative works. However, this document itself may not be modified in any way, such as by removing the copyright notice or references to the Internet Society or other Internet organizations, except as needed for the purpose of developing Internet standards in which case the procedures for copyrights defined in the Internet Standards process must be followed, or as required to translate it into languages other than English. The limited permissions granted above are perpetual and will not be revoked by the Internet Society or its successors or assigns. This document and the information contained herein is provided on an "AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. Klensin, et. al. Experimental [Page 14]