Abstract:Attribute revocation is crucial to use of ABE. The existing ABE schemes that support attributerevocation under the direct revocation model can only revoke the whole attributes that the user possesses byrevoking the user’s identity, so the attribute revocation is coarse-grained. This paper proposes the model of CP-ABEthat supports fully fine-grained attribute revocation. Based on the dual encryption system proposed by Waters, aconcrete CP-ABE scheme that fully supports fine-grained attribute revocation is constructed over the compositeorder bilinear groups, and the study proves its security under the standard model. Compared to the existing relatedschemes, this scheme is much more flexible and can revoke an arbitrary number of attributes that user possesses.