A Collusion-Resistant and Privacy-Preserving Data Aggregation Protocol in Crowdsensing System

With the pervasiveness and increasing capability of smart devices, mobile crowdsensing has been applied in more and more practical scenarios and provides a more convenient solution with low costs for existing problems. In this paper, we consider an untrusted aggregator collecting a group of users' data, in which personal private information may be contained. Most previous work either focuses on computing particular functions based on the sensing data or ignores the collusion attack between users and the aggregator. We design a new protocol to help the aggregator collect all the users' raw data while resisting collusion attacks. Specifically, the bitwise XOR homomorphic functions and aggregate signature are explored, and a novel key system is designed to achieve collusion resistance. In our system, only the aggregator can decrypt the ciphertext. Theoretical analysis shows that our protocol can capture k-source anonymity. In addition, extensive experiments are conducted to demonstrate the feasibility and efficiency of our algorithms.