WatersIBE方案的分析与改进  

Analysis and Improvement of Waters＇ IBE Scheme

作　　者：贡爽[1] 许春香[1] 

机构地区：[1]电子科技大学计算机科学与工程学院,四川成都611731

出　　处：《信息安全与通信保密》2009年第8期221-223,227,共4页Information Security and Communications Privacy

基　　金：国家863计划资助项目（2009AA012415）.

摘　　要：WaterSIBE方案是第一个在标准模型下可证明为完全安全的、基于身份的有效加密体制。丈中以直观启发的方式分析了Waters方案的安全性，这样的分析让人更能清楚地看到方案的安全性是如何与困难问题相联系的，为方案的安全性证明提供了坚实的基础。在不损失方案安全性的前提下，我们给出了方案改进的两个措施，第一个以幂指数运算代替方案中某项乘积运算，将这项运算的代价降为对数级，第二个避免了解密运算的求逆。Water＇ s IBE scheme is the first efficient identity-based encryption system, which is of fully provable security in the standard model. The scheme is analyzed in an intuitive and heuristic manner. This analysis enables one to more clearly learn how the scheme＇s security is related to the intractable problem, and provides a solid foundation for the scheme＇s security proving. Under the premise of no damage on the scheme＇ s security, two measures are given to improve the scheme＇ s efficiency, the first one is to substitute certain product term with an exponentation, and the cost of computation is then reduced to the order of logarithm; the second is to avoid inversion of the decryption.

关 键 词：直观分析 可证明安全 安全分析 密码体制 

分 类 号：TP311[自动化与计算机技术—计算机软件与理论]