RFC 9444 · PROPOSED STANDARD · 2023

Automated Certificate Management Environment for Subdomains

Overview

RFC 9444, “Automated Certificate Management Environment for Subdomains”, is a Proposed Standard document published in August 2023 by O. Friel, R. Barnes, T. Hollebeek, M. Richardson. The canonical text is published by the RFC Editor.

Abstract

This document specifies how Automated Certificate Management Environment (ACME) can be used by a client to obtain a certificate for a subdomain identifier from a certification authority. Additionally, this document specifies how a client can fulfill a challenge against an ancestor domain but may not need to fulfill a challenge against the explicit subdomain if certification authority policy allows issuance of the subdomain certificate without explicit subdomain ownership proof.

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 9444 is hosted at rfc-editor.org. Available in HTML,TXT,PDF,XML.

Other RFCs from 2023

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