Robust threshold signature scheme
Jianzhong Zhang · Computer Engineering and Applications Journal · 2009
Li et al have proposed an efficient threshold multi-signature based on the discrete logarithm,which can resist conspiracy attacks.On the other hand,they have claimed that their scheme could withstand several possible attacks.However,Michels and Horster have succeeded in producing a forgery,which shows that Li et al's scheme is insecure.This paper tries to improve the security of Li et al's scheme based on the factorization problem and the discrete logarithm modulo a large composite problem.The improved scheme prevents efficiently conspiracy attack while providing more efficient performance than other schemes in terms of computation complexity.