FIPS 204 (ML-DSA)

Definition

FIPS 204 is the NIST standard for ML-DSA (Module Lattice-Based Digital Signature Algorithm), previously known as Dilithium. Published in August 2024, FIPS 204 provides a quantum-resistant signature algorithm based on lattice mathematics, complementing hash-based SLH-DSA.

Technical Explanation

FIPS 204 specifies three security levels: ML-DSA-44 (Level 2), ML-DSA-65 (Level 3), and ML-DSA-87 (Level 5). Signatures are 2.4-4.6 KB—larger than ECDSA but smaller than hash-based alternatives. The algorithm uses Module-LWE hardness for security.

ML-DSA offers faster signing than hash-based schemes and smaller signatures, making it attractive for high-throughput applications. Security assumptions parallel Kyber's, providing consistent lattice-based cryptographic foundations.

SynX Relevance

SynX supports ML-DSA per FIPS 204 as an alternative to SPHINCS+ where smaller signatures or faster signing benefit specific applications. The default SPHINCS+ provides maximum conservatism; ML-DSA offers performance optimization when appropriate.

Frequently Asked Questions

ML-DSA vs SLH-DSA—which to choose?: ML-DSA for smaller signatures; SLH-DSA (SPHINCS+) for maximum security conservatism.
Are ML-DSA signatures quantum-resistant?: Yes—lattice problems resist quantum attacks; NIST evaluation confirmed security.
Is ML-DSA related to Kyber?: Both use module lattices, sharing mathematical foundations and security assumptions.

FIPS 204 compliant signatures available. Algorithm options with SynX