Mining Task Offloading in Mobile Edge Computing Empowered Blockchain

Blockchain is a decentralized digital ledger to capture and record economic transactions of mobile applications. In blockchain operation process, mining tasks play a key role and pose intensive computation demands on resource constrained mobile devices. Mobile edge computing (MEC) is a promising solution to alleviate the heavy burden on the devices through task offloading. Since only the miner device that first obtains a block can get rewards, there are risks of the devices for consuming edge computing resources without any profit. However, traditional task offloading schemes that purely rely on expected utilities of the devices always ignore the difference of various devices in balancing risks and rewards, thus make the offloading inefficient. To address this problem, we adopt a prospect theoretic approach to design an optimal offloading scheme for MEC-empowered blockchain, where diverse preferences of devices for profits and risks are explicitly taken into account. Specifically, we formulate the offloading process as a Stackelberg game that incorporates notions from prospect theory. We design an efficient algorithm to obtain the optimal offloading strategies, which maximize the utilities of both the miner devices and the MEC service providers. Numerical results are presented to illustrate the performance of the proposed offloading schemes.