RFC 9162 · EXPERIMENTAL · 2021

Certificate Transparency Version 2.0

Overview

RFC 9162, “Certificate Transparency Version 2.0”, is an Experimental document published in December 2021 by B. Laurie, E. Messeri, R. Stradling. It obsoletes RFC 6962. The canonical text is published by the RFC Editor.

Abstract

This document describes version 2.0 of the Certificate Transparency (CT) protocol for publicly logging the existence of Transport Layer Security (TLS) server certificates as they are issued or observed, in a manner that allows anyone to audit certification authority (CA) activity and notice the issuance of suspect certificates as well as to audit the certificate logs themselves. The intent is that eventually clients would refuse to honor certificates that do not appear in a log, effectively forcing CAs to add all issued certificates to the logs.

This document obsoletes RFC 6962. It also specifies a new TLS extension that is used to send various CT log artifacts.

Logs are network services that implement the protocol operations for submissions and queries that are defined in this document.

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

What “Experimental” means

Describes a specification that is part of a research or development effort, published so the community can gain experience with it.

Read this RFC

The canonical text of RFC 9162 is hosted at rfc-editor.org. Available in HTML,TXT,PDF,XML.

Relationships to other RFCs
This RFC obsoletes
RFC 6962
Other RFCs from 2021

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