Efficient cheater identification method for threshold schemes

Cheating detection is a very important issue for threshold schemes. An efficient and simple cheating detection and cheater identification method is proposed in this paper. The attack of the proposed method is as difficult as factoring the product of two large prime numbers, the intractability of which forms the basis for RSA. The proposed method is more efficient than Wu et al.´s and Hwang et al.´s methods (1995) in the verification phase. In addition, this method can prevent a conspirator from falsely accusing any specific shadow-holder