Online Certificate Status Protocol is an Internet Protocol and is used by certificate authorities to check the revocation status of specific digital certificates. The Online Responder Service is the component by Microsoft Windows service that is responsible for managing the configuration of OCSP responder by retrieving revocation information from revocation providers, signing responses, and auditing changes to the configuration of the OCSP responder.
The OCSP and CA uses Utimaco HSM for performing different operations like key generation, certificate signing, CRL signing and protecting their private keys.