ISO/IEC 9594-5:2017

Information technology — Open Systems Interconnection — The Directory — Part 5: Protocol specifications

ISO/IEC 9594-5:2017 specifies the Directory Access Protocol, the Directory System Protocol, the Directory Information Shadowing Protocol, and the Directory Operational Binding Management Protocol which fulfil the abstract services specified in Rec. ITU-T X.511 | ISO/IEC 9594-3, Rec. ITU-T X.518 | ISO/IEC 9594-4, Rec. ITU-T X.525 | ISO/IEC 9594-9, and Rec. ITU-T X.501 | ISO/IEC 9594-2.

Technologies de l'information — Interconnexion de systèmes ouverts (OSI) — L'annuaire — Partie 5: Spécifications du protocole

General Information

• Status: Withdrawn
• Publication Date: 04-May-2017
• Withdrawal Date: 04-May-2017
• ICS: 35.100.70 - Application layer
• Technical Committee: ISO/IEC JTC 1/SC 6 - Telecommunications and information exchange between systems
• Drafting Committee: ISO/IEC JTC 1/SC 6 - Telecommunications and information exchange between systems
• Current Stage: 9599 - Withdrawal of International Standard
• Completion Date: 01-Dec-2020

Relations

• Revised: ISO/IEC 9594-5:2020 - Information technology — Open systems interconnection — Part 5: The Directory: Protocol specifications
• Effective Date: 23-Apr-2020
• Revises: ISO/IEC 9594-5:2014 - Information technology — Open Systems Interconnection — The Directory — Part 5: Protocol specifications
• Effective Date: 10-Dec-2016
• Consolidated By: ISO 14246:2022 - Gas cylinders — Cylinder valves — Manufacturing tests and examinations
• Effective Date: 06-Jun-2022

Standards Content (Sample)

INTERNATIONAL ISO/IEC
STANDARD 9594-5
Eighth edition
2017-05
Information technology — Open
Systems Interconnection — The
Directory —
Part 5:
Protocol specifications
Technologies de l’information — Interconnexion de systèmes ouverts
(OSI) — L’annuaire —
Partie 5: Spécifications du protocole
Reference number
ISO/IEC 9594-5:2017(E)
©
ISO/IEC 2017

---------------------- Page: 1 ----------------------
ISO/IEC 9594-5:2017(E)

COPYRIGHT PROTECTED DOCUMENT
© ISO/IEC 2017, Published in Switzerland
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized otherwise in any form
or by any means, electronic or mechanical, including photocopying, or posting on the internet or an intranet, without prior
written permission. Permission can be requested from either ISO at the address below or ISO’s member body in the country of
the requester.
ISO copyright office
Ch. de Blandonnet 8 • CP 401
CH-1214 Vernier, Geneva, Switzerland
Tel. [phone]
Fax [phone]
[e-mail]
www.iso.org
ii © ISO/IEC 2017 – All rights reserved

---------------------- Page: 2 ----------------------
ISO/IEC 9594-5:2017(E)
Foreword
ISO (the International Organization for Standardization) and IEC (the International Electrotechnical
Commission) form the specialized system for worldwide standardization. National bodies that are
members of ISO or IEC participate in the development of International Standards through technical
committees established by the respective organization to deal with particular fields of technical
activity. ISO and IEC technical committees collaborate in fields of mutual interest. Other
international organizations, governmental and non‐governmental, in liaison with ISO and IEC, also
take part in the work. In the field of information technology, ISO and IEC have established a joint
technical committee, ISO/IEC JTC 1.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for
the different types of document should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject
of patent rights. ISO and IEC shall not be held responsible for identifying any or all such patent
rights. Details of any patent rights identified during the development of the document will be in the
Introduction and/or on the ISO list of patent declarations received (see www.iso.org/patents).
Any trade name used in this document is information given for the convenience of users and does
not constitute an endorsement.
For an explanation on the meaning of ISO specific terms and expressions related to conformity
assessment, as well as information about ISO's adherence to the World Trade Organization (WTO)
principles in the Technical Barriers to Trade (TBT) see the following
URL: www.iso.org/iso/foreword.html.
This eighth edition cancels and replaces the seventh edition (ISO/IEC 9594‐5:2014), which
has been technically revised.
This document was prepared by ISO/IEC JTC 1, Information technology, SC 6, Telecommunications
and information exchange between systems, in collaboration with ITU‐T. The identical text is
published as ITU‐T X.519 (10/2016).
A list of all parts in the ISO/IEC 9594 series, published under the general title Information technology
— Open Systems Interconnection — The Directory, can be found on the ISO website.
© ISO/IEC 2017 – All rights reserved ii-1

---------------------- Page: 3 ----------------------
CONTENTS
Page
1 Scope . 1
2 References . 1
2.1 Normative references . 1
2.2 Non-normative references . 2
3 Definitions . 2
3.1 Basic Directory definitions . 2
3.2 Distributed Operation Definitions . 3
3.3 Protocol specification definitions . 3
4 Abbreviations . 4
5 Conventions . 4
6 Common protocol specification. 5
6.1 Directory associations and operations . 5
6.2 Specification for Directory operations . 6
6.3 Directory protocol overview . 7
6.4 Operation codes . 8
6.5 Error codes . 8
6.6 Abstract syntaxes . 9
7 Directory protocols using the OSI stack . 9
7.1 OSI-PDUs . 9
7.2 Directory PDU structure . 9
7.3 Session PDUs . 10
7.4 OSI addressing . 11
7.5 Procedure and sequencing . 11
7.6 Directory PDU specifications . 11
8 Directory protocol mapping onto OSI services . 26
8.1 Abstract syntaxes and transfer syntaxes . 26
8.2 Application-context . 26
8.3 Session Layer specification . 28
8.4 Use of transport service . 34
8.5 OSI Transport Layer on top of TCP . 34
9 IDM protocol . 48
9.1 IDM-PDUs . 48
9.2 Sequencing requirements . 50
9.3 Protocols . 51
9.4 Reject reasons. 51
9.5 Abort reasons . 52
9.6 Mapping onto TCP/IP . 52
9.7 Addressing . 53
9.8 Use of TLS . 53
10 Directory protocol mapping onto the IDM protocol . 54
10.1 DAP-IP protocol . 54
10.2 DSP-IP protocol . 54
10.3 DISP-IP protocol . 55
10.4 DOP-IP protocol . 55
11 Protocol stack coexistence . 55
11.1 Coexistence between OSI and IDM stacks . 55
11.2 Coexistence in the presence of LDAP . 56
11.3 Defining network addresses for Internet Protocol, version 4 support . 56
11.4 Definition of NSAP-like address for long addressing information . 57
12 Versions and the rules for extensibility . 57
12.1 Use of extension markers . 57
 Rec. ITU-T X.519 (10/2016) iii

---------------------- Page: 4 ----------------------
Page
12.2 DUA to DSA . 58
12.3 DSA to DSA . 58
12.4 Rules of extensibility for NSAP addresses . 59
12.5 Rules of extensibility for object classes . 60
12.6 Rules of extensibility for user attribute types . 60
13 Conformance . 60
13.1 Conformance by DUAs . 60
13.2 Conformance by DSAs. 61
13.3 Conformance by a shadow supplier . 64
13.4 Conformance by a shadow consumer . 65
Annex A – Common protocol specifications in ASN.1 . 66
Annex B – OSI Protocol in ASN.1 . 68
Annex C – Directory OSI Protocols in ASN.1 . 74
Annex D – IDM Protocol in ASN.1 . 77
Annex E – Directory IDM Protocols in ASN.1 . 80
Annex F – Directory operational binding types . 82
Annex G – Amendments and corrigenda . 83

iv Rec. ITU-T X.519 (10/2016)

---------------------- Page: 5 ----------------------
Introduction
This Recommendation | International Standard, together with other Recommendations | International Standards, has been
produced to facilitate the interconnection of information processing systems to provide directory services. A set of such
systems, together with the directory information that they hold, can be viewed as an integrated whole, called the Directory.
The information held by the Directory, collectively known as the Directory Information Base (DIB), is typically used to
facilitate communication between, with or about objects such as application entities, people, terminals and distribution
lists.
The Directory plays a significant role in Open Systems Interconnection, whose aim is to allow, with a minimum of
technical agreement outside of the interconnection standards themselves, the interconnection of information processing
systems:
– from different manufacturers;
– under different managements;
– of different levels of complexity; and
– of different ages.
This Recommendation | International Standard specifies the application service elements and application contexts for two
protocols – the Directory Access Protocol (DAP) and the Directory System Protocol (DSP). The DAP provides for access
to the Directory to retrieve or modify Directory information. The DSP provides for the chaining of requests to retrieve or
modify Directory information to other parts of the distributed Directory System where the information may be held.
In addition, this Recommendation | International Standard specifies the application service elements and application
contexts for the Directory Information Shadowing Protocol (DISP) and the Directory Operational Binding Management
Protocol (DOP). The DISP provides for the shadowing of information held in one DSA to another DSA. The DOP
provides for the establishment, modification and termination of bindings between pairs of DSAs for the administration of
relationships between the DSAs (such as for shadowing or hierarchical relationships).
This Recommendation | International Standard provides the foundation frameworks upon which industry profiles can be
defined by other standards groups and industry forums. Many of the features defined as optional in these frameworks may
be mandated for use in certain environments through profiles. This eighth edition technically revises and enhances the
seventh edition of this Recommendation | International Standard.
This eighth edition specifies versions 1 and 2 of the Directory protocols.
The first and second editions specified only version 1. Most of the services and protocols specified in this edition are
designed to function under version 1. However some enhanced services and protocols, e.g., signed errors, will not function
unless all Directory entities involved in the operation have negotiated version 2. Whichever version has been negotiated,
differences between the services and between the protocols defined in the eight editions, except for those specifically
assigned to version 2, are accommodated using the rules of extensibility defined in this edition of Rec. ITU-T X.519 |
ISO/IEC 9594-5.
Annex A, which is an integral part of this Recommendation | International Standard, provides the ASN.1 module for the
common specifications for the Directory protocols.
Annex B, which is an integral part of this Recommendation | International Standard, provides the ASN.1 module for the
OSI protocol specification.
Annex C, which is an integral part of this Recommendation | International Standard, provides the ASN.1 module for the
Directory OSI protocols.
Annex D, which is an integral part of this Recommendation | International Standard, provides the ASN.1 module for the
IDM protocol specification.
Annex E, which is an integral part of this Recommendation | International Standard, provides the ASN.1 module for the
Directory IDM protocols.
Annex F, which is an integral part of this Recommendation | International Standard, provides the ASN.1 module which
contains all the ASN.1 object identifiers assigned to identify operational binding types in this series of Recommendations |
International Standards.
Annex G, which is not an integral part of this Recommendation | International Standard, lists the amendments and defect
reports that have been incorporated to form this edition of this Recommendation | International Standard.

 Rec. ITU-T X.519 (10/2016) v

---------------------- Page: 6 ----------------------
ISO/IEC 9594-5:2017 (E)
INTERNATIONAL STANDARD
RECOMMENDATION ITU-T
Information technology – Open Systems Interconnection – The Directory: Protocol
specifications
1 Scope
This Recommendation | International Standard specifies the Directory Access Protocol, the Directory System Protocol,
the Directory Information Shadowing Protocol, and the Directory Operational Binding Management Protocol which fulfil
the abstract services specified in Rec. ITU-T X.511 | ISO/IEC 9594-3, Rec. ITU-T X.518 | ISO/IEC 9594-4,
Rec. ITU-T X.525 | ISO/IEC 9594-9, and Rec. ITU-T X.501 | ISO/IEC 9594-2.
2 References
2.1 Normative references
The following Recommendations and International Standards contain provisions which, through reference in this text,
constitute provisions of this Recommendation | International Standard. At the time of publication, the editions indicated
were valid. All Recommendations and Standards are subject to revision, and parties to agreements based on this
Recommendation | International Standard are encouraged to investigate the possibility of applying the most recent edition
of the Recommendations and Standards listed below. Members of IEC and ISO maintain registers of currently valid
International Standards. The Telecommunication Standardization Bureau of the ITU maintains a list of currently valid
ITU-T Recommendations.
2.1.1 Identical Recommendations | International Standards
– Recommendation ITU-T X.200 (1994) | ISO/IEC 7498-1:1994, Information technology – Open Systems
Interconnection – Basic Reference Model: The basic model.
– Recommendation ITU-T X.213 (2001) | ISO/IEC 8348:2002, Information technology – Open Systems
Interconnection – Network service definition.
– Recommendation ITU-T X.214 (1995) | ISO/IEC 8072:1996, Information technology – Open Systems
Interconnection – Transport service definition.
– Recommendation ITU-T X.500 (2016) | ISO/IEC 9594-1:2017, Information technology – Open Systems
Interconnection – The Directory: Overview of concepts, models and services.
– Recommendation ITU-T X.501 (2016) | ISO/IEC 9594-2:2017, Information technology – Open Systems
Interconnection – The Directory: Models.
– Recommendation ITU-T X.509 (2016) | ISO/IEC 9594-8:2017, Information technology – Open Systems
Interconnection – The Directory: Public-key and attribute certificate frameworks.
– Recommendation ITU-T X.511 (2016) | ISO/IEC 9594-3:2017, Information technology – Open Systems
Interconnection – The Directory: Abstract service definition.
– Recommendation ITU-T X.518 (2016) | ISO/IEC 9594-4:2017, Information technology – Open Systems
Interconnection – The Directory: Procedures for distributed operation.
– Recommendation ITU-T X.520 (2016) | ISO/IEC 9594-6:2017, Information technology – Open Systems
Interconnection – The Directory: Selected attribute types.
– Recommendation ITU-T X.521 (2016) | ISO/IEC 9594-7:2017, Information technology – Open Systems
Interconnection – The Directory: Selected object classes.
– Recommendation ITU-T X.525 (2016) | ISO/IEC 9594-9:2017, Information technology – Open Systems
Interconnection – The Directory: Replication.
– Recommendation ITU-T X.690 (2015) | ISO/IEC 8825-1:2015, Information technology – ASN.1 encoding
rules: Specification of Basic Encoding Rules (BER), Canonical Encoding Rules (CER) and Distinguished
Encoding Rules (DER).
2.1.2 ISO/IEC Standards
– ISO/IEC 10646:2014, Information technology – Universal Multiple-Octet Coded Character Set (UCS).
 Rec. ITU-T X.519 (10/2016) 1

---------------------- Page: 7 ----------------------
ISO/IEC 9594-5:2017 (E)
2.1.3 Other references
– Recommendation ITU-T E.164 (2010), International operation – Numbering plan of the international
telephone service.
– Recommendation ITU-T X.121 (2000), International numbering plan for public data networks.
– Recommendation ITU-T X.680 (2015) | ISO/IEC 8824-1:2015, Information technology – Abstract Syntax
Notation One (ASN.1): Specification of basic notation.
– Recommendation ITU-T X.681 (2015) | ISO/IEC 8824-2:2015, Information technology – Abstract Syntax
Notation One (ASN.1): Information object specification.
– Recommendation ITU-T X.682 (2015) | ISO/IEC 8824-3:2015, Information technology – Abstract Syntax
Notation One (ASN.1): Constraint specification.
– Recommendation ITU-T X.683 (2015) | ISO/IEC 8824-4:2015, Information technology – Abstract Syntax
Notation One (ASN.1): Parameterization of ASN.1 specifications.
– IETF RFC 793 (1981), Transmission Control Protocol – DARPA Internet Program – Protocol
Specification.
– IETF RFC 1738 (1994), Uniform Resource Locators (URL).
– IETF RFC 2246 (1999), The TLS Protocol Version 1.0.
– IETF RFC 3546 (2003), Transport Layer Security (TLS) Extensions.
– IETF RFC 3986 (2005), Uniform Resource Identifier (URI): Generic Syntax.
2.2 Non-normative references
– Recommendation ITU-T X.217 (1995) | ISO/IEC 8649:1996, Information technology – Open Systems
Interconnection – Service definition for the Association Control Service Element.
– Recommendation ITU-T X.224 (1995) | ISO/IEC 8073:1997, Information technology – Open Systems
Interconnection – Protocol for providing the connection-mode transport service.
– Recommendation ITU-T X.225 (1995) | ISO/IEC 8327-1:1996, Information technology – Open Systems
Interconnection – Connection-oriented Session protocol: Protocol specification.
– Recommendation ITU-T X.226 (1994) | ISO/IEC 8823-1:1994, Information technology – Open Systems
Interconnection – Connection-oriented Presentation protocol: Protocol specification.
– Recommendation ITU-T X.227 (1995) | ISO/IEC 8650-1:1996, Information technology – Open Systems
Interconnection – Connection-oriented protocol for the Association Control Service Element: Protocol
specification.
– Recommendation ITU-T X.650 (1996) | ISO/IEC 7498-3:1997, Information technology – Open Systems
Interconnection – Basic Reference Model: Naming and addressing.
– Recommendation ITU-T X.881 (1994) | ISO/IEC 13712-2:1995, Information technology – Remote
Operations: OSI realizations – Remote Operations Service Element (ROSE) service definition.
– IETF RFC 896 (1984), Congestion Control in IP/TCP Internetworks.
– IETF RFC 1006 (1987), ISO Transport Service on top of the TCP Version: 3.
– IETF RFC 1277 (1991), Encoding Network Addresses to Support Operation over Non-OSI Lower Layers.
– IETF RFC 2126 (1997), ISO Transport Service on top of TCP (ITOT).
– IETF RFC 4511 (2006), Lightweight Directory Access Protocol (LDAP): The Protocol.
3 Definitions
For the purposes of this Recommendation | International Standard, the following definitions apply:
3.1 Basic Directory definitions
The following terms are defined in Rec. ITU-T X.501 | ISO/IEC 9594-2:
a) the Directory;
b) (Directory) user;
c) Directory System Agent (DSA);
2 Rec. ITU-T X.519 (10/2016)

---------------------- Page: 8 ----------------------
ISO/IEC 9594-5:2017 (E)
d) Directory User Agent (DUA).
3.2 Distributed Operation Definitions
The following terms are defined in Rec. ITU-T X.518 | ISO/IEC 9594-4:
a) chaining;
b) performer;
c) referral.
3.3 Protocol specification definitions
The following terms are defined in this Recommendation | International Standard.
NOTE – The terms defined in this clause are generalized definitions to cover both the OSI and the TCP/IP case, except where
exceptions are indicated.
3.3.1 abstract syntax: The specification of data types and/or data values by using notation rules which are
independent of the encoding technique used to represent them.
3.3.2 application-association: A cooperative relationship between two application-entities established by the Bind
operation.
3.3.3 application-context: (OSI only definition); a set of rules commonly shared by two application-entities in order
to support an application-association.
3.3.4 application-context-name: An ASN.1 object identifier that identifies (names) an application-context.
3.3.5 application layer: The top layer of the OSI seven layer model representing the semantics of the communication.
3.3.6 application-entity: A representation of the external behaviour of an application process in the form of its
communication capabilities.
3.3.7 application-entity title: The Directory distinguished name of an application-entity, and in particular, an
application-entity representing a Directory application process.
3.3.8 application process: A process within a system which performs information processing for a particular
purpose, in particular processing Directory operations.
3.3.9 Bind operation: An operation type used for establishing an application-association.
3.3.10 Directory operation: An operation type for the exchange of Directory information.
3.3.11 directory protocol-data-unit: A unit of data for a Directory protocol consisting of control information and in
general, also application data as specified by Directory operations.
NOTE 1 – A Directory PDU in the OSI environment includes all the protocol elements of the OSI Presentation Layer and if
relevant, protocol elements of ACSE in addition to the Directory-specific protocol elements.
NOTE 2 – The term "application-protocol-data-unit (APDU)" is a unit of data defined by an OSI application protocol. This term is
not used for edition 5 and subsequent editions of these Directory Specifications. However, the abbreviation may appear in certain
ASN.1 elements.
3.3.12 initiator: The application process that initiates an application-association by issuing a Bind request.
3.3.13 local matter: A decision made by a system concerning its behaviour that is not subject to the requirements of
these Directory Specifications.
3.3.14 operation: An exchange between two application processes to perform a particular task. It consists of a request
from one application-process to the other one and the return of zero or more responses (result and/or errors). An operation
implies a certain process to be performed by the application process receiving the request.
3.3.15 protocol-data-unit: Comprised of the presentation protocol elements or the ACSE protocol elements of a
Directory protocol-data-unit.
3.3.16 presentation layer: The sixth layer of the OSI Reference Model.
3.3.17 protocol error: An unrecognized or unexpected protocol-data-unit or a protocol-data-unit with an unexpected
or invalid parameter is received.
3.3.18 responder: The application-process that receives a Bind request and either accepts or refuses the
application-association.
 Rec. ITU-T X.519 (10/2016) 3

---------------------- Page: 9 ----------------------
ISO/IEC 9594-5:2017 (E)
NOTE – Initiator and responder are defined with respect to a single transport-connection. The initiator is also the application
process that initiated the transport-connection (see clause 8.4). A DSA can be both an initiator and responder simultaneously.
3.3.19 session layer: The fifth layer of the OSI Reference Model.
3.3.20 session-protocol-data-unit: (OSI only definition); a unit of data at the OSI Session
...