What is Public Key Infrastructure (PKI) and its main components?

• A. PKI is a firewall configuration.
• B. PKI is a framework for managing digital certificates and keys; components include certificate authorities, public/private keys, certificates, and certificate revocation lists.
• C. PKI is a password manager.
• D. PKI is a hardware security module.

Answer: (B)

Public Key Infrastructure is a framework that manages digital certificates and the keys used for secure communications. The essential parts are certificate authorities, which issue and sign certificates to establish trust in the binding between an identity and a public key; public and private keys, the asymmetric pair used for encryption and digital signatures; digital certificates themselves, which bind a public key to an identity and include information about the issuer and validity; and certificate revocation lists, which track certificates that are no longer trusted because the key was compromised or the identity is no longer valid. Together, these components enable trusted authentication, encrypted data transfer, and non-repudiation across networks. PKI is not a firewall configuration, a password manager, or a hardware security module, though a hardware security module can protect the private keys used within PKI.