Algorithm

FN-DSA (Falcon)

Family: lattice.

FN-DSA is the signature scheme based on Falcon, which NIST selected for standardization. Its main benefit is size: public keys and signatures are smaller than those of ML-DSA, which matters where each byte costs money, such as on a blockchain. The cost is harder signing code, because it samples from a Gaussian distribution using floating-point arithmetic. Verification is simple and fast.

Safety: Medium

Why this rating

Security rests on the hardness of problems over NTRU lattices, a structured-lattice family studied since the 1990s. Cryptanalysis is less mature than for hash functions. Signing needs careful floating-point Gaussian sampling, which is hard to implement in constant time, so side-channel and portability mistakes are a real risk.

Standard

https://falcon-sign.info/

Research

• Falcon: Fast-Fourier Lattice-based Compact Signatures over NTRU (specification)

Implemented by

• algorand/falcon
• liboqs
• PQClean
• pqhybridsign