通常情况下,用户所具有的属性集合由不同的认证机构负责分配和认证。针对这种情况,提出了一种多认证机构的属性加密方案。在该方案中,将属性全集分成若干个属性子集,而且各个属性子集之间相交结果是空集。对于每一个属性子集,由一认证机构负责监控用户的属性值并分配对应该属性值的密钥。任意发送者可用一属性集合加密信息,而具有该属性集合的用户可以解密已加密了的信息。所提方案满足IND—sSET—CPA安全。
A user's attributs are usually distributed and authenticated by the different authori- ties. Proposes a multi-authority attribute-based encryption scheme for this case. The universal attri- bute set is divided into a number of attribute subsets, moreover, the attribute subsets intersect is null set. For every attribute subset, an authority takes charge of monitoring the attribute value and as- signs a key corresponding to the attribute value. Every senter can encrypt the information with a cer- tain attribute set, and the user obtaining the attribute set can deerypt the encrypted information. The proposed scheme meets the security of IND-sSET-CPA.