Lightweight Fine-Grained Multiowner Search over Encrypted Data in Cloud-Edge Computing

Edge computing, as an extension of cloud computing, outsources encrypted sensitive data to edge nodes to decrease latency and improve broadband efficiency. Although attribute-based keyword search (ABKS) can ensure the security of outsourced data and promote fine-grained access control of data, deficiencies still exist under the general ABKS scheme in the cloud, as follows: shared files owned by a single data owner, inflexible access control, key escrow problem, and high computational overhead. We propose an attribute-based multidata owner searchable encryption scheme in cloud-edge computing with effective policy update to address these problems. The two-level access control is used to realize the common management and fine-grained sharing of data by the multidata owner. All user keys are jointly generated by the central authority and attribute authority, and a key escrow is no longer required. Moreover, partial encryption and decryption calculations are shifted from resource-constrained data owners and users to edge nodes. Furthermore, our scheme not only supports policy update but also realizes the dynamic updating of the index. The security proof and performance analysis show that the scheme has strong security and practicality in the edge computing environment.