rfc2967.txt

著名的RFC文档,其中有一些文档是已经翻译成中文的的.

Network Working Group                                          L. Daigle
Request for Comments: 2967                      Thinking Cat Enterprises
Category: Informational                                       R. Hedberg
                                                               Catalogix
                                                            October 2000


                 TISDAG - Technical Infrastructure for
                   Swedish Directory Access Gateways

Status of this Memo

   This memo provides information for the Internet community.  It does
   not specify an Internet standard of any kind.  Distribution of this
   memo is unlimited.

Copyright Notice

   Copyright (C) The Internet Society (2000).  All Rights Reserved.

Abstract

   The strength of the TISDAG (Technical Infrastructure for Swedish
   Directory Access Gateways) project's DAG proposal is that it defines
   the necessary technical infrastructure to provide a single-access-
   point service for information on Swedish Internet users.  The
   resulting service will provide uniform access for all information --
   the same level of access to information (7x24 service), and the same
   information made available, irrespective of the service provider
   responsible for maintaining that information, their directory service
   protocols, or the end-user's client access protocol.

Table of Contents

   1.0 Introduction. . . . . . . . . . . . . . . . . . . . . . . . .  5
   1.1 Project Goal. . . . . . . . . . . . . . . . . . . . . . . . .  5
   1.2 Executive Summary of Technical Study Result . . . . . . . . .  5
   1.3 Document Overview . . . . . . . . . . . . . . . . . . . . . .  6
   1.4 Terminology . . . . . . . . . . . . . . . . . . . . . . . . .  7
   2.0 Requirements. . . . . . . . . . . . . . . . . . . . . . . . .  7
   2.1 End-User Requirements . . . . . . . . . . . . . . . . . . . .  8
   2.2 WDSPs Requirements. . . . . . . . . . . . . . . . . . . . . .  8
   2.3 DAG-System Requirements . . . . . . . . . . . . . . . . . . .  9
   3.0 Functional Specification. . . . . . . . . . . . . . . . . . .  9
   3.1 Overview. . . . . . . . . . . . . . . . . . . . . . . . . . .  9
   3.2 The DAG Core. . . . . . . . . . . . . . . . . . . . . . . . . 10
   3.3 Client Interface. . . . . . . . . . . . . . . . . . . . . . . 11
   3.3.1 Acceptable User Input . . . . . . . . . . . . . . . . . . . 12



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      Supported Query Types. . . . . . . . . . . . . . . . . . . . . 12
      Matching Semantics . . . . . . . . . . . . . . . . . . . . . . 12
      Character Sets . . . . . . . . . . . . . . . . . . . . . . . . 13
   3.3.2 Data Output Spec. . . . . . . . . . . . . . . . . . . . . . 14
      Schema Definition. . . . . . . . . . . . . . . . . . . . . . . 14
      Referral Definition. . . . . . . . . . . . . . . . . . . . . . 14
      Error conditions . . . . . . . . . . . . . . . . . . . . . . . 14
   3.4 Directory Server Interface. . . . . . . . . . . . . . . . . . 14
   4.0 Architecture. . . . . . . . . . . . . . . . . . . . . . . . . 15
   4.1 Software Components . . . . . . . . . . . . . . . . . . . . . 15
   4.1.1 Internal Communications . . . . . . . . . . . . . . . . . . 15
   4.1.2 Referral Index. . . . . . . . . . . . . . . . . . . . . . . 15
   4.1.3 DAG-CAPs. . . . . . . . . . . . . . . . . . . . . . . . . . 15
   4.1.4 DAG-SAPs. . . . . . . . . . . . . . . . . . . . . . . . . . 17
   4.2 Important Architectural Notes . . . . . . . . . . . . . . . . 17
   4.2.1 2 Distinct Functions:  Referrals and Chaining . . . . . . . 17
   4.2.2 Limited Query and Response Semantics. . . . . . . . . . . . 17
   4.2.3 Visibility. . . . . . . . . . . . . . . . . . . . . . . . . 17
   4.2.4 Richness of Query semantics . . . . . . . . . . . . . . . . 18
   4.2.5 N+M Protocol Mappings . . . . . . . . . . . . . . . . . . . 18
   4.2.6 DAG-CAPs and DAG-SAPs are completely independent of each
      other. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
   4.2.7 The Role of the DAG-CAP . . . . . . . . . . . . . . . . . . 18
   4.2.8 The Role of the DAG-SAP . . . . . . . . . . . . . . . . . . 19
   4.2.9 DAG/IP is internal. . . . . . . . . . . . . . . . . . . . . 19
   4.2.10 Expectations . . . . . . . . . . . . . . . . . . . . . . . 19
   4.2.11 Future Extensions. . . . . . . . . . . . . . . . . . . . . 19
   5.0 Software Specifications . . . . . . . . . . . . . . . . . . . 19
   5.1 Notational Convention . . . . . . . . . . . . . . . . . . . . 19
   5.2 DAG-CAP Basics. . . . . . . . . . . . . . . . . . . . . . . . 20
   5.2.1 Functionality . . . . . . . . . . . . . . . . . . . . . . . 20
   5.2.2 Configuration . . . . . . . . . . . . . . . . . . . . . . . 21
   5.2.3 Error handling. . . . . . . . . . . . . . . . . . . . . . . 21
   5.2.4 Pruning of results. . . . . . . . . . . . . . . . . . . . . 22
   5.3 DAG-SAP Basics. . . . . . . . . . . . . . . . . . . . . . . . 22
   5.3.1 Functionality . . . . . . . . . . . . . . . . . . . . . . . 22
   5.3.2 Configuration . . . . . . . . . . . . . . . . . . . . . . . 23
   5.3.3 Error handling. . . . . . . . . . . . . . . . . . . . . . . 23
   5.3.4 Pruning of results. . . . . . . . . . . . . . . . . . . . . 23
   5.3.5 Constraint precedence . . . . . . . . . . . . . . . . . . . 23
   5.4 The Referral Index. . . . . . . . . . . . . . . . . . . . . . 24
   5.4.1 Architecture. . . . . . . . . . . . . . . . . . . . . . . . 24
   5.4.2 Interactions with WDSPs (CIP) . . . . . . . . . . . . . . . 24
   5.4.3 Index Object Format . . . . . . . . . . . . . . . . . . . . 24
   5.4.4 DAG-Internal I/O. . . . . . . . . . . . . . . . . . . . . . 24
   5.4.5 The Index Server. . . . . . . . . . . . . . . . . . . . . . 24
   5.4.6 Configuration . . . . . . . . . . . . . . . . . . . . . . . 25
   5.4.7 Security. . . . . . . . . . . . . . . . . . . . . . . . . . 25



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   5.5 Mail (SMTP) DAG-CAP . . . . . . . . . . . . . . . . . . . . . 25
   5.5.1 Mail DAG-CAP Input. . . . . . . . . . . . . . . . . . . . . 26
   5.5.2 Translation from Mail query to DAG/IP . . . . . . . . . . . 28
      Querying the Referral Index. . . . . . . . . . . . . . . . . . 28
      Querying a DAG-SAP . . . . . . . . . . . . . . . . . . . . . . 29
   5.5.3 Chaining queries in Mail DAG-CAP. . . . . . . . . . . . . . 31
   5.5.4 Expression of results in Mail DAG-CAP . . . . . . . . . . . 31
   5.5.5 Expression of Errors in Mail DAG-CAP. . . . . . . . . . . . 31
   5.6 Web (HTTP) DAG-CAP. . . . . . . . . . . . . . . . . . . . . . 32
   5.6.1 Web DAG-CAP Input . . . . . . . . . . . . . . . . . . . . . 32
   5.6.2 Translation from Web query to DAG/IP. . . . . . . . . . . . 33
      Querying a DAG-SAP Directly. . . . . . . . . . . . . . . . . . 33
      Querying the Referral Index. . . . . . . . . . . . . . . . . . 33
      Querying a DAG-SAP . . . . . . . . . . . . . . . . . . . . . . 35
   5.6.3 Chaining queries in Web DAG-CAP . . . . . . . . . . . . . . 36
   5.6.4 Expression of results in Web DAG-CAP. . . . . . . . . . . . 36
      text/html results. . . . . . . . . . . . . . . . . . . . . . . 36
      application/whoispp-response Results . . . . . . . . . . . . . 37
   5.6.5 Expression of Errors in Web DAG-CAP . . . . . . . . . . . . 37
      Standard Errors. . . . . . . . . . . . . . . . . . . . . . . . 38
   5.7 Whois++ DAG-CAP . . . . . . . . . . . . . . . . . . . . . . . 38
   5.7.1 Whois++ DAG-CAP Input . . . . . . . . . . . . . . . . . . . 38
   5.7.2 Translation from Whois++ query to DAG/IP. . . . . . . . . . 39
      Querying the Referral Index. . . . . . . . . . . . . . . . . . 39
      Querying a DAG-SAP . . . . . . . . . . . . . . . . . . . . . . 39
   5.7.3 Chaining in Whois++ DAG-CAP . . . . . . . . . . . . . . . . 40
   5.7.4 Expression of results in Whois++. . . . . . . . . . . . . . 41
   5.7.5 Expression of Errors in Whois++ DAG-CAP . . . . . . . . . . 41
   5.8 LDAPv2 DAG-CAP. . . . . . . . . . . . . . . . . . . . . . . . 42
   5.8.1 LDAPv2 DAG-CAP Input. . . . . . . . . . . . . . . . . . . . 42
   5.8.2 Translation from LDAPv2 query to DAG/IP . . . . . . . . . . 44
      Querying the Referral Index. . . . . . . . . . . . . . . . . . 44
      Querying a DAG-SAP . . . . . . . . . . . . . . . . . . . . . . 46
   5.8.3 Chaining queries in LDAPv2 DAG-CAP. . . . . . . . . . . . . 48
   5.8.4 Expression of results in LDAPv2 . . . . . . . . . . . . . . 48
   5.8.5 Expression of Errors in LDAPv2 DAG-CAP. . . . . . . . . . . 48
   5.9 LDAPv3 DAG-CAP. . . . . . . . . . . . . . . . . . . . . . . . 50
   5.9.1 LDAPv3 DAG-CAP Input. . . . . . . . . . . . . . . . . . . . 50
   5.9.2 Translation from LDAPv3 query to DAG/IP . . . . . . . . . . 51
      Querying the Referral Index. . . . . . . . . . . . . . . . . . 51
      Querying a DAG-SAP . . . . . . . . . . . . . . . . . . . . . . 54
   5.9.3 Chaining queries in LDAPv3 DAG-CAP. . . . . . . . . . . . . 55
   5.9.4 Expression of results in LDAPv3 . . . . . . . . . . . . . . 55
   5.9.5 Expression of Errors in LDAPv3 DAG-CAP. . . . . . . . . . . 56
   5.10 Whois++ DAG-SAP. . . . . . . . . . . . . . . . . . . . . . . 57
   5.10.1 Input. . . . . . . . . . . . . . . . . . . . . . . . . . . 57
   5.10.2 Translation from DAG/IP to Whois++ query . . . . . . . . . 58
   5.10.3 Translation of Whois++ results to DAG/IP . . . . . . . . . 58



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   5.11 LDAPv2 DAG-SAP . . . . . . . . . . . . . . . . . . . . . . . 59
   5.11.1 Input. . . . . . . . . . . . . . . . . . . . . . . . . . . 59
   5.11.2 Translation from DAG/IP to LDAPv2 query. . . . . . . . . . 59
   5.11.3 Translation of LDAPv2 results to DAG/IP. . . . . . . . . . 61
   5.12 LDAPv3 DAG-SAP . . . . . . . . . . . . . . . . . . . . . . . 62
   5.12.1 Input. . . . . . . . . . . . . . . . . . . . . . . . . . . 62
   5.12.2 Translation from DAG/IP to LDAPv3 query. . . . . . . . . . 62
   5.12.3 Translation of LDAPv3 results to DAG/IP. . . . . . . . . . 64
   5.13 Example Queries. . . . . . . . . . . . . . . . . . . . . . . 64
   5.13.1 A Whois++ Query. . . . . . . . . . . . . . . . . . . . . . 65
      What the Whois++ DAG-CAP Receives. . . . . . . . . . . . . . . 65
      What the Whois++ DAG-CAP sends to the Referral Index . . . . . 65
      What the Whois++ DAG-CAP Sends to an LDAP DAG-SAP. . . . . . . 65
   5.13.2 An LDAP Query. . . . . . . . . . . . . . . . . . . . . . . 66
      What the LDAP DAG-CAP Receives . . . . . . . . . . . . . . . . 66
   5.13.3 What the LDAP DAG-CAP sends to the Referral Index. . . . . 67
      What the LDAP DAG-CAP Sends to a Whois++ DAG-SAP . . . . . . . 67
      What the LDAP DAG-CAP Sends to an LDAP DAG-SAP . . . . . . . . 68
   6.0 Service Specifications. . . . . . . . . . . . . . . . . . . . 68
   6.1 Overview. . . . . . . . . . . . . . . . . . . . . . . . . . . 68
   6.2 WDSP Participation. . . . . . . . . . . . . . . . . . . . . . 69
   6.3 Load Distribution . . . . . . . . . . . . . . . . . . . . . . 69
   6.4 Extensibility . . . . . . . . . . . . . . . . . . . . . . . . 72
   7.0 Security. . . . . . . . . . . . . . . . . . . . . . . . . . . 73
   7.1 Information credibility . . . . . . . . . . . . . . . . . . . 73
   7.2 Unauthorized access . . . . . . . . . . . . . . . . . . . . . 73
   8.0 Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 74
   Appendix A - DAG Schema Definitions . . . . . . . . . . . . . . . 75
   A.1 DAG Personal Information Schema (DAGPERSON Schema). . . . . . 76
   A.2 DAG Organizational Role Information Schema (DAGORGROLE
      Schema). . . . . . . . . . . . . . . . . . . . . . . . . . . . 77
   Appendix B - Schema Mappings for Whois++ and LDAP . . . . . . . . 77
   B.1 LDAP and the DAG Schemas. . . . . . . . . . . . . . . . . . . 78
   B.2 Whois++ and the DAG Schemas . . . . . . . . . . . . . . . . . 81
   Appendix C - DAG-Internal Protocol (DAG/IP) . . . . . . . . . . . 82
   C.1 A word on the choice of DAG/IP. . . . . . . . . . . . . . . . 83
   C.2 DAG/IP Input and Output -- Overview . . . . . . . . . . . . . 83
   C.3 BNF for DAG/IP input and output . . . . . . . . . . . . . . . 83
   C.3.1 The DAG/IP Input Grammar. . . . . . . . . . . . . . . . . . 84
   C.3.2 The DAG/IP Response Grammar . . . . . . . . . . . . . . . . 87
   C.4 DAG/IP Response Messages. . . . . . . . . . . . . . . . . . . 89
   Appendix D - DAG/IP Response Messages Mapping . . . . . . . . . . 93
   Appendix E - DAG CIP Usage. . . . . . . . . . . . . . . . . . . . 95
   E.1 CIP Index Object. . . . . . . . . . . . . . . . . . . . . . . 95
   E.2 CIP Index Object Creation . . . . . . . . . . . . . . . . . . 97
   E.3 CIP Index Object Sharing. . . . . . . . . . . . . . . . . . . 98
   E.3.1 Registration of Servers . . . . . . . . . . . . . . . . . . 98
   E.3.2 Transmission of Objects . . . . . . . . . . . . . . . . . .100



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   Appendix F - Summary of Technical Survey Results. . . . . . . . .100
   Appendix G - Useful References. . . . . . . . . . . . . . . . . .102
   Bibliography. . . . . . . . . . . . . . . . . . . . . . . . . . .102
   Authors' Addresses. . . . . . . . . . . . . . . . . . . . . . . .104
   Full Copyright Statement. . . . . . . . . . . . . . . . . . . . .105

List of Tables

   Table 3.1 DAG-supported queries . . . . . . . . . . . . . . . . .12
   Table 5.1 Allowable Whois++ Queries . . . . . . . . . . . . . . .38
   Table A.1 DAGPERSON schema attributes . . . . . . . . . . . . . .76
   Table A.2 DAGORGROLE schema attributes. . . . . . . . . . . . . .77
   Table B.1 Canonical DAGPERSON schema & LDAP inetorgPerson
      attributes . . . . . . . . . . . . . . . . . . . . . . . . . .79
   Table B.2 Reasonable Approximations for LDAP organizationalRole
      attributes . . . . . . . . . . . . . . . . . . . . . . . . . .79
   Table B.3 Canonical mappings for LDAP organizationalRole
      attributes . . . . . . . . . . . . . . . . . . . . . . . . . .81
   Table B.4 Canonical DAGPERSON schema & Whois++ USER attributes. .81
   Table B.5 Canonical mappings for Whois++ ORGROLE attributes . . .82
   Table C.1 List of system response codes . . . . . . . . . . . . .90
   Table D.1 LDAPv2/v3 resultcodes to DAG/IP response codes
      mapping. . . . . . . . . . . . . . . . . . . . . . . . . . . .93
   Table D.2 Mapping from DAG/IP response codes to LDAPv2/v3
      resultcodes. . . . . . . . . . . . . . . . . . . . . . . . . .94
   Table D.3 Mapping between DAG/IP and Whois++ response codes . . .94
   Table F.1 Summary of TISDAG Survey Results: Queries . . . . . . 101
   Table F.2 Summary of TISDAG Survey Results: Operational
      Information. . . . . . . . . . . . . . . . . . . . . . . . . 101

1.0 Introduction

1.1 Project Goal

   The overarching goal of this project is to develop the necessary
   technical infrastructure to provide a single-access-point service for
   searching for whitepages information on Swedish Internet users.  The
   service must be uniform for all information -- the same level of
   access to information (7x24 service), and the same whitepages
   information made available, irrespective of the service provider
   responsible for maintaining that information.

1.2 Executive Summary of Technical Study Result

   The strength of the TISDAG project's DAG proposal is that it defines
   the necessary technical infrastructure to provide a single-access-
   point service for information on Swedish Internet users.  The
   resulting service will provide uniform access for all information --



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   the same level of access to information (7x24 service), and the same
   information made available, irrespective of the service provider
   responsible for maintaining that information, their directory service
   protocols, or the end-user's client access protocol.

   Instead of requiring centralized mirroring of complete information
   records from Swedish directory service providers, the DAG system uses
   a well-defined index object summary of that data, updated at the
   directory service provider's convenience.  When an end-user queries
   the DAG, the referral information is used (by the end-user's
   software, or by a module within the DAG, as appropriate) to complete
   the final query directly at the directory service provider's system.
   This ensures that the end-user gets the most up-to-date complete
   information, and promotes the directory service provider's main
   interest:  its service.  The architecture of the DAG itself is very
   modular; support for future protocols can be added in the operational
   system.

1.3 Document Overview

   This document is broken into 5 major sections:

   Requirements: As a service, the DAG system will have several
   different types of users.  In order to be successful, those users'
   needs (requirements) must be met.  This in turn defines certain
   constraints, or system requirements, that must be met.  This section
   aims to capture the baseline requirement assumptions to be addressed
   by the system, and thus lays the groundwork on which the rest of the
   proposed system is built.

   Functional Specification Overview: Working from the users'
   requirements, specific technologies and  functionality details are
   outlined to architect a system that will meet the stated