What is the role of the Registration Authority (RA) in a PKI system?

• A. Stores public keys for practitioners
• B. Issues and signs certificates
• C. Maintains the certificate revocation list in real time
• D. Verifies identities before issuing certificates

Answer: (D)

In a PKI, the Registration Authority serves as the identity vetting gatekeeper. Its main job is to verify the applicant’s identity and eligibility before any certificate is issued, making sure the requester meets the organization’s policies and requirements. Once identity is confirmed, the certificate is issued and signed by the Certificate Authority, which is the entity that actually creates and cryptographically signs the certificate. The RA does not store public keys as a primary function, since public keys are part of the certificate itself and distributed with the certificate. Likewise, real-time maintenance of the certificate revocation list is handled by the CA and the PKI revocation infrastructure, not by the RA.