Public Key Infrastructure (PKI)
TLDR: Public Key Infrastructure (PKI) is a system of technologies, policies, and procedures designed to create, manage, distribute, and revoke digital certificates and public-private key pairs. It provides the foundation for secure communications, authentication, and data integrity in digital ecosystems. PKI is widely used in TLS/SSL, email encryption, digital signatures, and secure access control systems.
https://en.wikipedia.org/wiki/Public_key_infrastructure
The core components of PKI include a Certificate Authority (CA), which issues and signs digital certificates, and a Registration Authority (RA), which verifies the identity of entities requesting certificates. Certificates bind public keys to specific entities, ensuring that communications are secure and authentic. The use of asymmetric encryption ensures that only the intended recipient can decrypt a message, while the sender’s identity can be verified through a signature.
https://csrc.nist.gov/glossary/term/public-key-infrastructure
PKI enables secure interactions in various applications, such as authenticating users and devices in enterprise networks, encrypting sensitive data, and ensuring software integrity during updates. To maintain trust, PKI employs mechanisms like certificate revocation lists (CRLs) and online certificate status protocols (OCSP) to manage compromised certificates or expired certificates. As the backbone of digital security, PKI remains essential for protecting sensitive information in an increasingly connected world.
https://www.nist.gov/itl/special-publications/nist-special-publication-800-32