Submitting a PKI certificate request
When requesting a certificate, an entity introduces itself to the CA by providing its identity information and public key, which will be the major components of the certificate. A certificate request can be submitted to a CA in offline mode or online mode. In offline mode, a certificate request is submitted to a CA by an "out-of-band" means such as phone, disk, or email.
An online certificate request can be submitted in manual mode or auto mode.