Public Key Infrastructure (PKI)
PKI is a comprehensive framework of roles, policies, and procedures used to create, manage, distribute, use, store, and revoke DIGITAL-CERTIFICATES. It provides the essential foundation for secure information exchange over the INTERNET by leveraging ASYMMETRIC-CRYPTOGRAPHY to ensure confidentiality, integrity, and authenticity. Organizations rely on PKI to establish trust in digital environments.
Core Components
The architecture of a PKI involves several critical entities. The CERTIFICATE-AUTHORITY (CA) acts as a trusted third party that signs and issues PUBLIC-KEY-CERTIFICATES. Before issuance, a REGISTRATION-AUTHORITY (RA) verifies the identity of the requester. To maintain the security of the ecosystem, the CERTIFICATE-REVOCATION-LIST (CRL) and the OCSP protocol are employed to identify and manage certificates that are no longer valid.
Standards and Applications
Most modern PKI systems adhere to the X.509 standard, which defines the format for digital certificates. This standard is integral to the functioning of SSL-TLS, the protocol suite used to secure web traffic, and S-MIME, which provides encryption for email. For technical specifications, researchers often cite the NIST PKI Project and the IETF RFC 5280 as primary sources of authority.