rfc2258.txt

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3.  Registering a CCSO Server

   The Internet Nomenclator Project supports the following home page:

      http://cm.bell-labs.com/cs/what/nomenclator

   The home page provides a variety of information and services.

   Administrators can register their CCSO servers through services on
   this home page.  The registration service collects CCSO server
   location information, contact information for the administrator of
   the CCSO server, implicit and explicit constraints on entries in the
   server's database, and a mapping from the local schema of the CCSO
   server to the schema of the world view.

   The implicit and explicit constraints on the server's database are
   the fuel for Nomenclator's catalog functions.  The registration
   center currently collects constraints on organization name,
   department, city, state or province name, country, phone number,
   postal code, and email address.  These constraints are automatically
   incorporated into Nomenclator's distributed catalog service.  They
   are used by catalog functions in query resolvers to constrain
   searches to relevant CCSO servers.  For example, a database only
   contains information about the computer science and electrical
   engineering departments at a French university.  The department,
   organization and country attributes are constrained.  Nomenclator
   uses these constraints to prevent queries about other departments,
   organizations or countries from being sent to this CCSO server.

   The mapping from the local schema of the CCSO server to the schema of
   the world view allows Nomenclator to translate queries and responses
   for the CCSO server.  The registration center currently collects this
   mapping by requesting an example of how to translate a typical entry
   in the CCSO server into the world view schema and, optionally, an
   example of how to translate a canonical entry in the world view
   schema into the local schema of the CCSO server [4].  These examples
   are then used to generate a mapping program that is stored in the
   distributed catalog service.  The CCSO data access function in the
   query resolver interprets these programs to translate queries and
   responses communicated with that CCSO server.  We plan to release the
   mapping language to CCSO server administrators, so administrators can
   write and maintain the mapping for their servers.  We have
   experimented with more than 20 mapping programs.  They are seldom
   more than 50 lines, and are often shorter.  It typically takes one or
   two lines to map an attribute.






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RFC 2258              Internet Nomenclator Project          January 1998


4.  Using Nomenclator

   The Internet Nomenclator Project currently provides a centralized
   query service on the Internet.  The project runs a Nomenclator query
   resolver that is accessible through its Web page (see the URL in
   Section 3) and the Simple Nomenclator Query Protocol (SNQP) [2].

   The service answers queries that are a conjunction of string values
   for attributes.  A variety of matching techniques are supported
   including exact string matching, matching with wildcards, and word-
   based matching in the style of the CCSO service.  Our web interface
   uses the Simple Nomenclator Query Protocol (SNQP) [2].  Programmers
   can create their own interfaces by using this protocol to communicate
   with the Nomenclator query resolver.  They will require the host name
   and port number for the query resolver which they can obtain from the
   Nomenclator home page.  SNQP, and hence the web interface, are
   defined for US-ASCII.  Support for other character sets will require
   further work.

   Subsequent phases of the project will provide enhanced services such
   as providing advice about the cost of queries and ways to constrain
   queries further to produce faster response times, and allowing users
   to request more current data.  We also plan to distribute query
   resolvers, so users can benefit from running query resolvers locally.
   Local query resolvers reduce latency for the user, and distribute
   query processing load throughout the network.

5.  Summary

   The Internet Nomenclator Project augments existing CCSO services by
   supplying schema integration and fast cross-server searches. The key
   to speed in descriptive query processing is an active catalog, and
   extensive meta-data and data caching.  The Nomenclator system is the
   result of research in distributed systems [5][6][7][4].  It can be
   extended to incorporate other name servers, besides the CCSO servers,
   and to address distributed search and retrieval challenges in other
   application domains. In addition to providing a white pages service,
   the Internet Nomenclator Project will evaluate how an active catalog,
   meta-data caching and data caching perform in very large global
   information system.  The ultimate goal of the project is to refine
   these techniques to provide the best possible global information
   systems.









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RFC 2258              Internet Nomenclator Project          January 1998


6.  Security Considerations

   In the Internet Nomenclator Project, the participants' data are
   openly available and read-only. Since the risk of tampering with
   queries and responses is considered low, this version of Nomenclator
   does not define procedures for protecting the information in its
   queries and responses.

7.  References


   [1]   H. Garcia-Molina, G. Wiederhold. "Read-Only Transactions in
         a Distributed Database,"  ACM Transactions on Database Systems
         7(2), pp. 209-234.  June 1982.

   [2]   Elliott, J., and J. Ordille, "The Simple Nomenclator Query
         Protocol (SNQP)," RFC 2259, January 1998.

   [3]   S. Dorner, P. Pomes. "The CCSO Nameserver: A Description,"
         Computer and Communications Services Office Technical Report,
         University of Illinois, Urbana, USA. 1992. Avaialble in the
         current "qi" distribution from
         <URL:ftp://uiarchive.cso.uiuc.edu/local/packages/ph>

   [4]   A. Levy, J. Ordille. "An Experiment in Integrating Internet
         Information Sources," AAAI Fall Symposium on AI Applications in
         Knowledge Navigation and Retrieval, November 1995.
         <URL:http://cm.bell-labs.com/cm/cs/doc/95/11-01.ps.gz>

   [5]   J. Ordille. "Descriptive Name Services for Large Internets,"
         Ph. D. Dissertation. University of Wisconsin. 1993.
         <URL:http://cm.bell-labs.com/cm/cs/doc/93/12-01.ps.gz>

   [6]   J. Ordille, B. Miller. "Distributed Active Catalogs and
         Meta-Data Caching in Descriptive Name Services," Thirteenth
         International IEEE Conference on Distributed Computing Systems,
         pp. 120-129.  May 1993.
         <URL:http://cm.bell-labs.com/cm/cs/doc/93/5-01.ps.gz>

   [7]   J. Ordille, B. Miller. "Nomenclator Descriptive Query
         Optimization in Large X.500 Environments," ACM SIGCOMM
         Symposium on Communications Architectures and Protocols, pp.
         185-196, September 1991.
         <URL:http://cm.bell-labs.com/cm/cs/doc/91/9-01.ps.gz>







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RFC 2258              Internet Nomenclator Project          January 1998


8.  Author's Address

   Joann J. Ordille
   Bell Labs, Lucent Technologies
   Computing Sciences Research Center
   700 Mountain Avenue, Rm 2C-301
   Murray Hill, NJ 07974  USA

   EMail: [e-mail]










































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RFC 2258              Internet Nomenclator Project          January 1998


9.  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.
























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