研究成果

Hazay et al. proposed zero-knowledge proof protocols extending MPC-in-the-Head using game-based cryptographic primitives. Its communication does not directly rely on its circuit size. We reduced the communication complexity of HSS-based ZKP, one of Hazay’s protocols, by reducing the interaction in randomness generation. Specifically, we replaced interactive random numbers with a pseudorandom function whose input is the prover’s randomness. This achieves reducing communication size, but fails to satisfy the zero knowledge property. By applying the Fiat-Shamir transformation, we obtain full zero knowledge in the random oracle model while preserving the communication improvement.