BPT: A Blockchain-Based Privacy Information Preserving System for Trust Data Collection Over Distributed Mobile-Edge Network

Contemporarily, fast development of computing, communication and storage technology has revolutionized the way that various data-based applications reach massive data from underlying sensor networks. However, such process also raises two challenging but critical issues: trustworthy and privacy issue for data collectors. Therefore, this paper pro-poses a novel system, which is designed over the distributed mobile edge network to sufficiently exploit advantages of blockchain and differential privacy to collect trustworthy data and protect privacy for data collectors. Firstly, to im-prove trustworthy of data collections, a new consensus mechanism is proposed for blockchain-based data collection structure, which comprehensively incorporates trustworthy, collection contribution, and throughput together to prefer data collectors for the next block. Secondly, with assistance of fully trusted devices, a verifiable trustworthy evaluation strategy is designed to accurately compute the trustworthy for data collec-tors. Thirdly, we enforce differential privacy on the data stored in global blockchain maintained by the cloud server to protect privacy for data collectors without influencing data availability. Finally, both theoretical analyses and experi-mental results prove that the proposed system comprehen-sively improves performance of data collections in distributed network without adding any additional cost for cloud server, compared to other schemes.