Endorsing Certificate

This mechanism uses secure messages using symmetric key for integrity and confidentiality protection, and uses an endorsing client certificate to augment the claims provided by the token associated with the message signature. For this mechanism, the client knows the service’s certificate, and requests need to be endorsed/authorized by a special identity. For example, all requests to a vendor must be endorsed by a purchase manager, so the certificate of the purchase manager should be used to endorse (or counter sign) the original request.