Several Properties of ∑-protocol

Abstract

∑-protocol is an important tool in cryptology field.In this paper,we will prove that any ∑-protocol has the following characters: ①it is a witness hiding protocol if there exist at least two witnesses on R;②there exists a ∑-protocol on any NP statement under the assumption of the existence of one-way permutation;③there exist ∑-protocols with computational zero-knowledge;④∑-protocol can be changed into a zero-knowledge proof.