ISO/IEC 9594-4:2020/Amd 1:2025
(Amendment)Information technology — Open systems interconnection — Part 4: The Directory: Procedures for distributed operation — Amendment 1: Miscellaneous enhancements
Information technology — Open systems interconnection — Part 4: The Directory: Procedures for distributed operation — Amendment 1: Miscellaneous enhancements
Technologies de l'information — Interconnexion de systèmes ouverts (OSI) — Partie 4: Titre manque — Amendement 1: Titre manque
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International
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ISO/IEC 9594-4
Ninth edition
Information technology — Open
2020-11
systems interconnection —
AMENDMENT 1
Part 4:
2025-05
The Directory: Procedures for
distributed operation
AMENDMENT 1: Miscellaneous
enhancements
Reference number
ISO/IEC 9594-4:2020/Amd. 1:2025(en) © ISO/IEC 2025
ISO/IEC 9594-4:2020/Amd. 1:2025(en)
© ISO/IEC 2025
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© ISO/IEC 2025 – All rights reserved
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ISO/IEC 9594-4:2020/Amd. 1:2025(en)
Foreword
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Commission) form the specialized system for worldwide standardization. National bodies that are
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see www.iso.org/iso/foreword.html. In the IEC, see www.iec.ch/understanding-standards.
This document was prepared by ITU-T as ITU-T X.518 (2019) Amd. 1 (10/2024) and drafted in
accordance with its editorial rules, in collaboration with Joint Technical Committee ISO/IEC
JTC 1, Information technology, Subcommittee SC 6, Telecommunications and information
exchange between systems.
A list of all parts in the ISO/IEC 9594 series can be found on the ISO and IEC websites.
Any feedback or questions on this document should be directed to the user’s national standards body.
A complete listing of these bodies can be found at www.iso.org/members.html and
www.iec.ch/national-committees.
Rec. ITU-T X.518 (2019) Amd. 1 (10/2024)
© ISO/IEC 2025 – All rights reserved
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ISO/IEC 9594-4:2020/Amd. 1:2025(en)
INTERNATIONAL STANDARD ISO/IEC 9594-4
RECOMMENDATION ITU-T X.518
Information technology – Open Systems Interconnection – The Directory:
Procedures for distributed operation
Amendment 1
Miscellaneous enhancements
Summary
Amendment 1 to Recommendation ITU-T X.518 (2019) | International Standard ISO/IEC 9594-4:2020 introduces text
updates to facilitate separation between cybersecurity ASN.1 modules and directory ASN.1 modules
History
Edition Recommendation Approval Study Group Unique ID
1.0 ITU-T X.518 1988-11-25 11.1002/1000/3005
2.0 ITU-T X.518 1993-11-16 7 11.1002/1000/3006
3.0 ITU-T X.518 1997-08-09 7 11.1002/1000/4125
3.1 ITU-T X.518 (1997) Technical Cor. 1 2000-03-31 7 11.1002/1000/5038
3.2 ITU-T X.518 (1997) Amd. 1 2000-03-31 7 11.1002/1000/5037
3.3 ITU-T X.518 (1997) Technical Cor. 2 2001-02-02 7 11.1002/1000/5316
4.0 ITU-T X.518 2001-02-02 7 11.1002/1000/5318
4.1 ITU-T X.518 (2001) Technical Cor. 1 2005-05-14 17 11.1002/1000/8505
4.2 ITU-T X.518 (2001) Cor. 2 2008-05-29 17 11.1002/1000/9435
5.0 ITU-T X.518 2005-08-29 17 11.1002/1000/8506
5.1 ITU-T X.518 (2005) Cor. 1 2008-05-29 17 11.1002/1000/9436
5.2 ITU-T X.518 (2005) Cor. 2 2011-02-13 17 11.1002/1000/11046
6.0 ITU-T X.518 2008-11-13 17 11.1002/1000/9596
6.1 ITU-T X.518 (2008) Cor. 1 2011-02-13 17 11.1002/1000/11047
6.2 ITU-T X.518 (2008) Cor. 2 2012-10-14 17 11.1002/1000/11739
7.0 ITU-T X.518 2012-10-14 17 11.1002/1000/11740
8.0 ITU-T X.518 2016-10-14 17 11.1002/1000/13034
9.0 ITU-T X.518 2019-10-14 17 11.1002/1000/14035
9.1 ITU-T X.518 (2019) Amd. 1 2024-10-29 17 11.1002/1000/16174
To access the Recommendation, type the URL https://handle.itu.int/ in the address field of your web browser, followed by the
Recommendation's unique ID.
Rec. ITU-T X.518 (2019) Amd. 1 (10/2024)
© ISO/IEC 2025 – All rights reserved
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ISO/IEC 9594-4:2020/Amd. 1:2025(en)
FOREWORD
The International Telecommunication Union (ITU) is the United Nations specialized agency in the field of
telecommunications, and information and communication technologies (ICTs). The ITU Telecommunication
Standardization Sector (ITU-T) is a permanent organ of ITU. ITU-T is responsible for studying technical,
operating and tariff questions and issuing Recommendations on them with a view to standardizing
telecommunications on a worldwide basis.
The World Telecommunication Standardization Assembly (WTSA), which meets every four years, establishes
the topics for study by the ITU-T study groups which, in turn, produce Recommendations on th
...
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