Credibility optimization and power control for secure mobile crowdsourcing

Recent emergence of mobile crowdsourcing applications has made it imperative to ensure security and efficient resource allocation to the users involved in such applications, especially considering the nature of wireless transmission that is power limited and highly vulnerable to eavesdropping. Although there have been some efforts to maximize the report credibility along with power allocation to reporters involved in such applications, security along with long-term system utility maximization is still unexplored. In this paper, we ensure security in mobile crowdsourcing and maximize the utility (incorporating both credibility and power consumption) by provisioning secure transmission rate to each user based on power selection and reporting format selection, considering current channel condition. We propose an online decision algorithm, called FLAPO (Format Selection and Power Control for Credibility Optimization), to optimally choose report format and secrecy rate optimization whenever an event takes place. Leveraging the recently developed Lyapunov optimization technique, we prove that FLAPO achieves the close-to-optimal system utility while bounding the average queue backlog (which translates into average reporting delays). We also perform a simulation study to complement the analysis and the simulation results are consistent with our theoretical analysis.