中文摘要：

为得到电子商务中高效、安全的数字签名方案,在改进后的Schnorr签名方案的基础上,提出一种新型门限数字签名方案,其最大特点是满足成员单独签名并具有前向安全性。为防止签名权力被滥用,方案采取二次分割的方式对密钥进行分配,成员必须与签名中心合作才能完成签名,确保方案具备可审计性并能抵御成员合谋攻击;为提升方案的鲁棒性,成员与服务器在签名过程中执行Joint-Shamir-RSS协议,共享关键随机参数k,保证了签名过程的安全性并使得方案能够抵御外部攻击。与同类方案相比,所提方案具有密钥分发简单、签名过程高效、可动态增删成员等优点。

英文摘要：

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.