Which fields are contained on a digital certificate?

• A. Public key
• B. Digital signature
• C. Serial number
• D. All of the above

Answer: (D)

Digital certificates are structured to bind a public key to a verified identity and to prove that binding hasn't been altered. The fields commonly present include the subject's public key, the issuer's digital signature over the certificate contents, and a serial number assigned by the issuer. The public key is the cryptographic key that others will use to encrypt data for the certificate holder or to verify their signatures. The digital signature is created by the issuing authority over the certificate data; it can be verified with the issuer’s public key to confirm the certificate hasn’t been tampered with and that the issuer attested to the binding. The serial number uniquely identifies this certificate within the issuing CA’s records and is used in revocation processes and certificate management. Because these elements are part of a digital certificate, all of the above correctly describes the fields contained.