一种新型群签名的分析与改进*

最近提出的一种新型群签名方案，首先对Boneh-Boyen短签名提出了一种变形方案，然后在此变形方案的基础上构造一种群签名方案，使得它不依赖于可信第三方来为群成员产生证书。指出了此变形方案本身是错误的，故在此基础上的群签名也是不成立的。除此之外，所构造的群签名方案本身也存在签名长度过长、同一签名成员的签名存在关联性的缺陷。最后，给出了改进的方案。

Cryptanalysis and improvement on new type of group signature scheme

The recently proposed new type of group signature scheme was constructed on a new signature derived from the Boneh-Boyen short signature scheme. However, the new signature scheme was fault thus the group signature was flawed. Besides, the proposed group signature scheme was long in length and the signatures of the same signer are linkable. Further, this paper proposed an improved scheme.