NIST finalized three post-quantum cryptographic standards in August 2024: ML-KEM (FIPS 203) for key exchange, ML-DSA (FIPS 204) for digital signatures, and SLH-DSA (FIPS 205) as a hash-based backup. The 'harvest now, decrypt later' (HNDL) threat means organizations with long-retention sensitive data must act before quantum computers exist. US National Security Systems face a January 2027 CNSA 2.0 compliance deadline for new acquisitions. Authentication systems specifically at risk include TLS handshakes, JWT/SAML token signing, X.509 certificates, and FIDO2 passkeys (all ECC/RSA-based). A six-step migration roadmap covers cryptographic asset inventory, crypto agility in new systems, hybrid deployments (ML-KEM + X25519), PKI migration, authentication system updates, and vendor assessment. AES-256 remains safe; the migration scope is asymmetric cryptography only.
Table of contents
What Quantum Computers Actually Threaten (And What They Do Not)The NIST PQC Standards: What Is Final, What to Deploy NowThe Compliance Timeline: When Organizations Must ActAuthentication-Specific PQC: What Needs to ChangeThe Harvest Now Decrypt Later Threat: Why Action Cannot WaitThe Six-Step Enterprise PQC Migration RoadmapAlgorithm Selection Quick ReferenceFrequently Asked QuestionsWhat to Read NextSort: