Joint computation offloading and content caching for wireless blockchain networks

Blockchain is widely deemed as a key enabling technology of current digital currency. However, the application of blockchain to wireless mobile networks is challenged by a computational difficult problem called proof-of-work puzzle. Accordingly, mobile edge computing (MEC) appears to be a promising solution by offloading the computation-intensive mining tasks to nearby edge computing nodes. Meanwhile, caching is also popular due to its capability in handling the ever-increasing Internet traffic. In this paper, we study computation offloading and content caching in wireless blockchain networks with MEC. Specifically, offloading mode selection (offloaded to a nearby access point (AP) or a group of device-to-device (D2D) users) and caching strategy (whether to cache the requested content and computation results or not) are jointly investigated and formulated as an optimization problem. Further, an alternating direction method of multipliers (ADMM) based algorithm is proposed to solve the optimization problem in a distributed way. Finally, the effectiveness of the proposed algorithm is demonstrated by simulation results with different system parameters.