Public Key Authentication: What It Is and How It Works

Public key authentication uses asymmetric cryptography with mathematically linked key pairs to verify identity without transmitting passwords. The system works by having clients prove possession of a private key through cryptographic signatures that can be verified with a corresponding public key. This eliminates password-related vulnerabilities like phishing, credential stuffing, and data breaches. The technology underpins modern security systems including HTTPS/TLS, SSH, passkeys, JWT signatures, code signing, and email encryption. Key advantages include strong cryptographic identity verification, non-repudiation, and elimination of shared secrets over networks.