Information technology — Open Systems Interconnection — The Directory: Public-key and attribute certificate frameworks

Verified on 2026-10-29

(title available in French only)

Official Binding

Reference
ITU-T X.509 (10/2019)
Type
Other standard
Folder
Other standards
Version
en vigueur
Date
2019-10
Status
Final
Languages
English
Official source
https://www.itu.int/rec/T-REC-X.509-201910-I/en

Note

ITU-T Recommendation X.509 (October 2019), which defines frameworks for public-key certificates and attribute certificates, including revocation lists and public key infrastructure.

The full text is not reproduced here (copyright): see the official source.

Summary

Purpose

Recommendation ITU-T X.509, whose text is common with standard ISO/IEC 9594-8, defines the frameworks for public-key certificates and attribute certificates. The edition in the corpus, the ninth, was approved on 14 October 2019 (edition 10/2019) ITU-T X.509 (10/2019) ITU-T X.509 (10/2019), § 1 Scope. Its scope states:

Official text · ITU-T X.509 (10/2019), § 1 Scope

The public-key certificate framework defined in this Recommendation | International Standard specifies the information objects and data types for a public-key infrastructure (PKI), including public-key certificates, certificate revocation lists (CRLs), trust broker and authorization and validation lists (AVLs).

A public-key infrastructure (PKI) is the whole that makes it possible to issue, manage and revoke certificates binding a public key to an entity. The Recommendation also sets the framework for issuing, managing, using and revoking certificates, as well as a set of certificate and revocation list extensions ITU-T X.509 (10/2019), § 1 Scope.

Who it applies to

It serves as a basis for applications using strong authentication based on cryptographic techniques, without claiming to make it a general authentication framework. It is up to the users of an application to define their own security policy ITU-T X.509 (10/2019), § 1 Scope.

Under eIDAS, Implementing Decision 2015/1505 sets the specifications for the Member States’ trusted lists; these lists meet the specifications of its Annex I Art. 1. If a Member State publishes a human readable form of its list, it contains the same data as the form intended for automated processing Art. 3(2). Chapter IV of Annex I then provides that this form displays as a minimum certain fields of the digital certificates in the “Service digital identity” field: version, serial number, signature algorithm, issuer, validity period, subject, public key, key usage, CRL distribution points…; a footnote refers, for these certificates, to “Recommendation ITU-T X.509 | ISO/IEC 9594-8” Annex I.

What the act takes from the Recommendation

  • Clauses: no particular clause; the footnote refers to the whole Recommendation Annex I.
  • Adaptations: none Annex I.
  • Edition: the footnote cites none; the corpus contains the 10/2019 edition Annex I ITU-T X.509 (10/2019).
  • Condition: the requirement applies only when a human readable form of the list is established and published Annex I.

Other acts in the corpus mention X.509 certificates, for example Implementing Regulation 2024/2977 Annex, but no other act names Recommendation ITU-T X.509 itself (finding as at 31-10-2026) Annex I.

Key points

Consolidation without official value

This summary cites the consolidated version, published on EUR-Lex, of Implementing Decision 2015/1505 Implementing Decision (EU) 2015/1505 — consolidated version of 29/04/2026. It serves as documentation: only the text published in the Official Journal is authentic.

Written by Asphalia.