I. Introduction
Mobile cloud computing (MCC) is known as an effective solution to bridge the gap between the resource-constrained mobile devices and the resource-demanding applications by offloading the compute-intensive tasks to the remote clouds [1] . However, MCC faces a large communication latency issue because of the long distance between mobile devices and remote clouds. Hence, for real-time and delay sensitive applications, MCC is not suitable for computation offloading. Mobile edge computing (MEC), which move cloud resource to the vicinity of the mobile network, can address the high latency issue [2] . Since MEC servers are located at the edge of mobile networks, the response time of cloud-based mobile applications is greatly reduced. Besides offering computing resource, the MEC server is able to provide storage and caching service, and help base station to allocate power and bandwidth resource to mobile users [3] .