Attribute-based Access Control of Data Sharing Based on Hyperledger Blockchain

While public cloud service provides scholars a means to collaborate and share studies, depositing their data on a centralized semi-trusted cloud server managed by third party, raises security and privacy issues; secure decentralized storage can overcome this risky problem. In this paper, we propose an architecture model providing more fine-grained access control over the data stored in the cloud. Our proposed system is implemented by combining Hyperledger blockchain technology and Attribute-based Encryption (ABE) scheme to achieve this fine-grained access control of the shared files in decentralized environment. The implementation of the ABE prevents unauthorized users from accessing data and allows data owners to manage and control their data by encrypting shared data under an access control policy associated with a set of attributes. The Hyperledger blockchain assures the confidentiality and integrity of all stored files including key generation, policy assignment, and access request service. Our system prototype was implemented using chaincodes and tested on the Hyperledger Composer blockchain platform.