【摘要】 在一个(t,n)门限代理签名方案中,原始签名人授权n个代理签名人,使得任意t或更多个代理签名人可合作产生对消息的代理签名。基于Zhang和Kim的门限代理签名方案,Sun提出了一个新的门限代理签名方案。但Sun的方案易受到合谋攻击,在此之后的修改方案在安全性、效率等方面不能令人满意。新的改进方案在弥补安全漏洞的同时保持较高的效率。更多还原

【Abstract】 In a(t,n) threshold proxy signature scheme,t or more proxy signers from a designated group of n proxy signers can generate proxy signatures on behalf of the original signer.Based on Zhang’s and Kim’s threshold proxy signature schemes,Sun proposed a new threshold proxy signature scheme.But Sun’s scheme suffers from conspiracy attack,and the improvements proposed hereafter are not satisfying.A new improvement is proposed to conquer the disadvantage of Sun’s scheme and keep higher efficiency.更多还原