A Learning Algorithm for Real-time Service In Vehicular Networks with Mobile-Edge Computing

Mobile edge computing (MEC) is an emerging paradigm to offload the server-side resources closer to the mobile terminals compared with cloud-based computing. However, due to highly vehicular mobility and limited wireless coverage, it is challenging to apply off-the-shelf MEC-based architecture to support the real-time services in vehicular networks, especially when the vehicle density changes dynamically. Hence, this paper investigates a novel service scenario in an MEC-based architecture, where the local MEC server has to complete the real-time services of mobile vehicles in its service range. On this basis, we formulate a novel problem of distributed real-time service scheduling (DRSS) by comprehensively considering the delay requirements of real-time services, the heterogeneous computing capabilities of MEC servers and the mobility features of vehicles, which targets at maximizing the service ratio. To resolve such an issue, we propose a multi-agent reinforcement learning algorithm called Utility-based Learning (UL), in which each local MEC server selects the optimal solution by learning the global knowledge online. Specifically, a utility table is established to determine the optimal solution by estimating the pending delay of service request at each MEC server and it will be updated periodically based on the feedback signal from the assigned MEC server. Lastly, we build the simulation model and conduct an extensive performance evaluation, which demonstrates the superiority of the proposed algorithm.