independent ISRG ISRG ISRG The Automatic Certificate Management Environment (ACME) protocol allows server operators to obtain TLS certificates for their websites, based on a demonstration of control over the website's domain via a fully-automated challenge/response protocol. OpenID Federation 1.0 defines how to build a trust infrastructure using a trusted third-party model. It uses a trust evaluation mechanism to attest to the possession of private keys, protocol specific metadata and miscellaneous administrative and technical information related to a specific entity. This document defines how X.509 certificates associated with a given OpenID Federation Entity can be issued by an X.509 Certification Authority through the ACME protocol to the organizations which are part of a federation built on top of OpenID Federation 1.0.