An efficient KP design framework of attribute-based searchable encryption for user level revocation in cloud

Attribute-based searchable encryption (ABSE) is the combination of attribute-based encryption (ABE) and searchable encryption with the inherent benefits of fine-grained access control and expressive searching capabilities in multiuser setting. In this paper, we have used the key-policy (KP) design framework of ABE and named the scheme KP-ABSE. The proposed KP-ABSE scheme efficiently supports user revocation where the computationally intensive tasks are delegated to the cloud server. Furthermore, the proposed scheme generates constant-size user secret keys and trapdoors and has constant number of pairing operations, which in other schemes typically varies with the number of attributes associated with them. Thus, the proposed scheme reduces computational and storage costs and supports fast searching. Finally, the proposed scheme can be proven secure under a decision linear assumption in a selective security model.