Which of the following binds a subject name to a public key value?

A.
A public-key certificate

B.
A public key infrastructure

C.
A secret key infrastructure

D.
A private key certificate

Explanation:
A typical PKI consists of hardware, software, policies and standards to manage the creation, administration,
distribution and revocation of keys and digital certificates. Digital certificates are at the heart of PKI as they
affirm the identity of the certificate subject and bind that identity to the public key contained in the certificate.
Incorrect Answers:
A: A public-key certificate contains a public key. However, it is the PKI (in particular the certificate authority) that
verifies the subject’s identity and binds the subject name to the public key value.
C: A secret key infrastructure is not a valid answer. A secret key can refer to a private key or more commonly to
a shared key used in symmetric encryption.
D: A private key (and its corresponding public key) is usually generated by a user or application. The public key
is then validated and signed by a CA. A private key does not bind a subject name to a public key value.

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