ToMAS: Torus-based secure multi-factor biometric authentication system
Mi Yeon Hong, Kang Hoon Lee, Ji Hyuk Jung, Ji Won Yoon · Computational and Structural Biotechnology Journal · 2025
phases through cryptographic protocols. ToMAS adopts a multi-factor approach using both physiological biometric traits and password-derived secrets, and leverages fully homomorphic encryption (FHE) to perform computations on encrypted data without revealing sensitive information. To reduce overhead and improve efficiency, we introduce a ciphertext packing method and a modified bootstrapping technique for secure Hamming distance evaluation. Our protocol is analyzed against active adversaries. Experiments show that a 9600-bit binary biometric template can be encrypted into an 82KB ciphertext, and the Hamming distance between encrypted templates is computed in under one second on a standard AMD Ryzen Threadripper Pro CPU, with no loss of accuracy. ToMAS offers an efficient and scalable solution suitable for large-scale biometric authentication scenarios.