Post-Quantum Algorithms

Quantum-resistant cryptographic algorithms designed to withstand attacks from quantum computers.

Available Post-Quantum Algorithms

Key Encapsulation Mechanisms (KEMs)

ML-KEM-768 (Kyber)

NIST-standardized lattice-based key encapsulation mechanism.

  • Security Level: NIST Level 3 (192-bit equivalent)
  • Public Key: 1,184 bytes
  • Ciphertext: 1,088 bytes
  • Shared Secret: 32 bytes
  • Use Cases: TLS, VPN, secure messaging

Digital Signatures

Dilithium (ML-DSA)

NIST-standardized lattice-based digital signature algorithm.

  • Security Levels: 2, 3, 5 (128, 192, 256-bit equivalent)
  • Public Key: 1,312 bytes (Level 2)
  • Signature: 2,420 bytes (Level 2)
  • Use Cases: Code signing, document authentication

Falcon-512

Compact lattice-based signatures with smaller key sizes.

  • Security Level: NIST Level 1 (128-bit equivalent)
  • Public Key: 897 bytes
  • Signature: ~690 bytes (variable)
  • Use Cases: Constrained environments, IoT

Alternative KEMs

NTRU Prime

Alternative lattice-based KEM with different security assumptions.

  • Security Level: 128-bit equivalent
  • Public Key: 1,230 bytes
  • Ciphertext: 1,047 bytes
  • Use Cases: Diversification, research applications

Algorithm Comparison

Algorithm Type Security Level Public Key Size Signature/CT Size
ML-KEM-768 KEM 192-bit 1,184 bytes 1,088 bytes
Dilithium-2 Signature 128-bit 1,312 bytes 2,420 bytes
Dilithium-3 Signature 192-bit 1,952 bytes 3,293 bytes
Falcon-512 Signature 128-bit 897 bytes ~690 bytes
NTRU Prime KEM 128-bit 1,230 bytes 1,047 bytes

Security Considerations

Quantum Threat Timeline

  • Current: Classical computers cannot break these algorithms
  • Near-term: Quantum computers pose no immediate threat
  • Long-term: Large-scale quantum computers would break RSA/ECC

Migration Strategy

  1. Hybrid Approach: Combine classical + post-quantum algorithms
  2. Gradual Transition: Start with less critical applications
  3. Algorithm Agility: Design systems to easily swap algorithms
  4. Performance Testing: Evaluate impact on system performance

Performance Characteristics

Speed Rankings

  1. ML-KEM-768: Fast key generation and encapsulation
  2. NTRU Prime: Moderate performance
  3. Falcon-512: Fast verification, slower signing
  4. Dilithium: Moderate performance, larger sizes

Memory Requirements

  • Low: Falcon-512 (stack-based)
  • Medium: ML-KEM-768, NTRU Prime
  • High: Dilithium (matrix operations)

Use Case Recommendations

For TLS/Network Protocols

  • Primary: ML-KEM-768 for key exchange
  • Signatures: Dilithium-2 or Falcon-512
  • Hybrid: Combine with X25519 + Ed25519

For Code Signing

  • Recommended: Dilithium-3 (higher security)
  • Alternative: Falcon-512 (smaller signatures)
  • Transition: Dual signatures during migration

For IoT/Embedded

  • Preferred: Falcon-512 (compact)
  • Alternative: ML-KEM-768 (if memory allows)
  • Consideration: Power and bandwidth constraints

For Long-term Storage

  • Recommended: Dilithium-5 (highest security)
  • Backup: Multiple algorithm signatures
  • Future-proofing: Plan for algorithm updates

Implementation Status

All post-quantum algorithms in MetaMUI Crypto Primitives are:

  • ✅ NIST-compliant implementations
  • ✅ Constant-time where applicable
  • ✅ Cross-platform compatible
  • ✅ Extensively tested with official test vectors
  • ✅ Ready for production use

Standards and Specifications