RFC 9163 · EXPERIMENTAL · 2022

Expect-CT Extension for HTTP

Overview

RFC 9163, “Expect-CT Extension for HTTP”, is an Experimental document published in June 2022 by E. Stark. The canonical text is published by the RFC Editor.

Abstract

This document defines a new HTTP header field named "Expect-CT", which allows web host operators to instruct user agents (UAs) to expect valid Signed Certificate Timestamps (SCTs) to be served on connections to these hosts. Expect-CT allows web host operators to discover misconfigurations in their Certificate Transparency (CT) deployments. Further, web host operators can use Expect-CT to ensure that if a UA that supports Expect-CT accepts a misissued certificate, that certificate will be discoverable in Certificate Transparency logs.

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 9163 is hosted at rfc-editor.org. Available in HTML,TXT,PDF,XML.

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