标准模型下可证安全的基于身份门限环签名

在门限环签名中,任意n个成员组中的t个成员可以代表整个成员组产生(t,n)门限环签名,而对实际的签名者却具有匿名性。目前,基于身份的门限环签名方案大都是在随机预言模型下对其安全性进行证明的,然而在随机预言模型下可证安全的方案却未必是安全的,因此设计标准模型下的门限环签名方案更有意义。利用双线性对技术,提出了一种安全、高效的基于身份门限环签名方案,并在标准模型下基于计算Diffie-Hellman难问题证明方案满足适应性选择消息和身份攻击下的存在不可伪造性;同时,也对方案的无条件匿名性进行了证明。

Provably secure identity-based threshold ring signature in the standard model

The (t,n) threshold ring signature can be generated by any t entities of n entities group on behalf of the whole group, while the actual signers remain anonymous. At present, the security of the identity based threshold ring signature schemes are almost proven under the random oracle model, while it may be not secure for those schemes under the random oracle model. There, it is meaningful to design threshold ring signature scheme in the standard model. This paper proposes a secure and efficient identity-based threshold ring signature scheme by using bilinear pairing technique, and proves that this scheme satisfies the existential unforgeability against adaptive chosen message and identity attacks in terms of the hardness of CDH problem in the standard model. Meanwhile, it is proved that the scheme satisfies the unconditional signer ambiguity.