支持高效撤销的多机构属性加密方案

摘要

Multi-authority attribute-based encryption was very suitable for data access control in a cloud storage environment.However,efficient user revocation in multi-authority attribute-based encryption remains a challenging problem that prevents it from practical applications.A multi-authority ciphertext-policy attribute-based encryption scheme with efficient revocation was proposed in prime order bilinear groups,and was further proved statically secure and revocable in the random oracle model.Extensive efficiency analysis results indicate that the proposed scheme significantly reduce the computation cost for the users.In addition,the proposed scheme supports large universe and any monotone access structures,which makes it more flexible for practical applications.%多机构属性加密方案非常适用于云存储环境下的数据访问控制.然而,高效的用户撤销仍是其中一个具有挑战的问题,这妨碍了多机构属性加密的实际应用.针对此问题,在素数阶群中提出一种支持高效撤销的多机构密文策略属性加密方案,并在随机预言模型下证明了方案是静态性安全和支持撤销的.分析结果表明所提方案极大地降低了用户的计算开销.此外,所提方案支持大属性域和所有单调访问结构,因此,在实际应用中更加灵活.