Which process is used to obtain a certificate from a CA?

Enrollment is the specific process where an entity (user, device, server) requests and receives a digital certificate from a Certificate Authority (CA), typically involving generating a key pair, creating a Certificate Signing Request (CSR), and submitting it to the CA. The CA then verifies the requestor's identity and issues the certificate, binding the public key to the entity's identity.

Registration is a broader term that might be part of the enrollment process (e.g., registering an identity), but enrollment specifically refers to the certificate acquisition.

Approval is a step within the enrollment process where the CA validates and approves the certificate request.

Signing is the action the CA performs to digitally sign the certificate, but it's part of the broader enrollment process, not the overall process name.