An Attribute-Based Keyword Search Scheme for Multiple Data Owners in Cloud-Assisted Industrial Internet of Things

The cloud-assisted industrial Internet of Things (IIoT) architecture can sustain highly available computation and massive storage services for modern industrial systems. When data owners store IIoT data to remote cloud platforms, the data security will face tough challenges. Cryptographic technologies endow an ability to guarantee data confidentiality. However, traditional encryption techniques make data access control and data searching malfunctioning. Recently emerging attribute-based keyword search (ABKS) primitive achieves fine-grained access control and effective data searching over ciphertexts. However, existing ABKS schemes only consider single data owner scenarios and may be an inappropriate choice for IIoT applications, where there exists multiple data owners for an integrated industrial system. Directly extending state-of-the-art single owner schemes to ones for multiowner environment will impose a complicated key management issue. We present an ABKS scheme for multiowners in the cloud-assisted IIoT architecture. By designing a novel master key generation and private key aggregation mechanism with desired communication overheads, our scheme eliminates the complex key management issue in the multiowner model. Formal security proof demonstrates that our scheme is secure against the cloud server. Experimental evaluations also demonstrate its correctness and practicality.