关键词: 单独签名, 大整数因子分解问题, 前向安全, 二次分割, 动态增删成员, 电子商务

Abstract: To meet the demand from nowadays e-commerce for efficient and secure signature scheme, a novel threshold signature scheme based on the scheme of improved Schnorr signature was proposed. The scheme achieved forward-secure property and enabled a single member to complete signature efficiently. To prevent signing authority from being abusing, a twice-splitting way was utilized to distribute the secret key, which made the member needs to cooperate with the signature center to issue a valid electronic check. Thus the scheme had auditability and capability of resisting conspiracy attack. To improve the robustness of the scheme, the security of signing process was enhanced by executing Joint-Shamir-RSS protocol to share the key random parameter k, and a security problem was also solved. Compared to the congeners, the key distribution of the proposed scheme was much more convenient, the signature process was higher efficient, and the members could be added and revoked dynamically.

Key words: sign independently, integer factorization problem, forward security, twice-splitting, add and revoke members dynamically, e-commerce