Privacy-Preserving Task Allocation and Decentralized Dispute Protocol in Mobile Crowdsourcing

Mobile crowdsourcing is an emerging network architecture that can outsource tasks to a group of people or devices. Most recent literature studied the location privacy of users during task allocation in mobile crowdsourcing. But in some cases, a dispute may occur when users have an argument about the payment of the task. To adjudicate the dispute, users need to provide their private information such as credentials to the third party. Furthermore, finding a trusted third party for mobile crowdsourcing is hard in real life, raising the opportunity for decentralized disputes. However, existing work cannot avoid information leakage during decentralized dispute adjudication, and these schemes can also lower the efficiency of arbitrating. In this paper, we propose a privacy-preserving and decentralized dispute arbitration protocol, which allows the dispute adjudication to proceed without a trusted third party but prevents users' private information from disclosing. Specifically, we first propose a secure task allocation protocol for mobile crowdsourcing, which preserves users' location privacy while enabling efficient task release and allocation. Then, in order to avoid employing a trusted third party, we design a privacy-preserving and decentralized dispute arbitration protocol, which does not reveal any private information during the dispute adjudication. Security and privacy discussions show our protocol can resist forgery attacks but preserve privacy during the decentralized dispute adjudication. In addition, performance evaluation validates the efficiency of our protocol.