An efficient undeniable group-oriented signature scheme

摘要

Three main methods with favorable security and efficiency can be considered in the design of cryptosystems. These methods are integer factorization systems (of which RSA is the best known example), discrete logarithm systems (such as DSA) and elliptic curve cryptosystems (ECC) [Math. Comput. 48 (1987) 203; Advances in Cryptology-Crypto’85, Springer-Verlag, 1986 p. 417]. The elliptic curve cryptosystem has been applied in this study because of its low computational cost and short key size, which reduces the overheads in a limited-hardware environment. Thus, the elliptic curve constitutes a suitable environment for the cryptosystems.This study improves the undeniable signature scheme [Proceedings of the Eleventh National Conference on Information Security, 2001, p. 331] by reducing its time complexity. Such an improvement makes the proposed scheme more efficient and secure.