高效安全的基于身份的签名方案

Efficient and Secure Identity-Based Signature Scheme

Paterson等人在Waters签名方案的基础上提出的基于身份的签名方案,虽然在标准模型下被证明能够归约于CDH问题假定,但方案的计算效率不高.此后,李-姜等人对Paterson方案虽然进行了改进,但方案的在线计算效率不高.在Paterson方案的基础上,提出了一种在标准模型下更高效的基于身份的签名方案.该方案采用转变原方案中的群元素乘法运算为整数加法运算的方法来提高计算效率,而且利用预先计算双线性对的方法来改进方案的在线计算性能.与Paterson方案相比,消除了多次乘法运算,减少了验证方的双线性对计算次数;与李-姜方案相比,减少了签名方和验证方的在线运算量以及系统输出参数;同时,该方案在标准模型下被证明具有在自适应选择消息攻击下存在不可伪造性,其安全性能够归约于CDH问题假定.与现有的标准模型下基于身份的签名方案相比,该方案的计算效率更高.

Paterson,et al.have studied identity-based signature scheme based on Waters’ signature scheme in a standard model,which has proved to have a security reduction to CDHP assumption,but has low computational efficiency.Although Li-Jiang,et al.improves Paterson’s scheme,Li-Jiang’s scheme has low online computational efficiency.This paper shows a more efficient identity-based signature scheme based on Paterson’s scheme in standard model.The new scheme improves computational efficiency by changing multiplicative operation to addition operation and pre-computing bilinear pairing operation.The scheme comparing with Paterson’s scheme decreases the number of multiplicative operation and the number of bilinear pairing operation of verifier.The scheme comparing with Li-Jiang’s scheme decreases the on-line computation of signer and verifier and the output parameters of system.Also,the scheme has proved to have a security reduction to CDHP assumption and the existential unforgeability under an adaptive chosen message attack.Comparing with other identity-based signature schemes in standard model,the new scheme is more efficient.