RFC 9562 · PROPOSED STANDARD · 2024

Universally Unique IDentifiers

Overview

RFC 9562, “Universally Unique IDentifiers”, is a Proposed Standard document published in May 2024 by K. Davis, B. Peabody, P. Leach. It obsoletes RFC 4122. The canonical text is published by the RFC Editor.

Abstract

This specification defines UUIDs (Universally Unique IDentifiers) -- also known as GUIDs (Globally Unique IDentifiers) -- and a Uniform Resource Name namespace for UUIDs. A UUID is 128 bits long and is intended to guarantee uniqueness across space and time. UUIDs were originally used in the Apollo Network Computing System (NCS), later in the Open Software Foundation's (OSF's) Distributed Computing Environment (DCE), and then in Microsoft Windows platforms.

This specification is derived from the OSF DCE specification with the kind permission of the OSF (now known as "The Open Group"). Information from earlier versions of the OSF DCE specification have been incorporated into this document. This document obsoletes RFC 4122.

Abstract as published in the RFC, via rfc-editor.org.

What “Proposed Standard” means

An entry-level standards-track specification: stable, peer-reviewed and a solid basis for implementation, though it may still evolve before becoming an Internet Standard.

Read this RFC

The canonical text of RFC 9562 is hosted at rfc-editor.org. Available in HTML,TXT,PDF,XML.

Relationships to other RFCs
This RFC obsoletes
RFC 4122
Other RFCs from 2024

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