Trading Fairness and Sharing Accountability in Decentralized Secure Data Sharing

In the modern era of big data, guaranteeing data sharing fairness and accountability of the shared data are important for ensuring user privilege and marketplace supervision. On one hand, due to the Internet’s nature, where data sharing usually occurs, every user might be potentially malicious and cheat others. As a result, there is limited trust between data-sharing participants, and ensuring fairness among them without a centralized trusted third party is non-trivial. On the other hand, with the increasing awareness of the data owners’ control over their data and the demands of market-wise regulation, guaranteeing accountability, traceability, and trackability of the sharing behaviors is also necessary. Although different protocols have been proposed to address such concerns, they can be further improved in many aspects. In this dissertation, I present several lines of research around ensuring trading fairness and sharing accountability during the whole decentralized data-sharing life cycle. I detail research on ensuring traceability and trackability of the sharing behaviors, guaranteeing secure and efficient fairness between untrusted trading participants, and further proposing various designs with the consideration of different trading scenarios. These improvements and innovations promote better guarantees for fairness and accountability of online data sharing.