Public Key Infrastructure PKI

Cryptography 🔒 • Difficulty: premium

Definition

PKI is a framework that uses cryptographic key pairs and digital certificates to secure communication, verify identity, and enable trust in digital environments.

Examples

  • A website uses a digital certificate issued by a trusted Certificate Authority to prove its identity to users' browsers.
  • An employee uses a smart card with a digital certificate to log securely into a corporate network.

Overview

Public Key Infrastructure, or PKI, is a system for managing digital keys and certificates that enable secure communication and trust online. It forms the foundation of secure internet protocols like HTTPS and supports services such as digital signatures, encrypted email, secure authentication, and code signing.

PKI relies on a pair of cryptographic keys: a public key, which is shared openly, and a private key, which is kept secret. These key pairs allow users to encrypt data, verify identities, and ensure the integrity of information without needing to pre-share secrets. At the core of PKI is the digital certificate, which binds a public key to an identity and is issued by a trusted authority.

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