QoS-Aware Joint Power Allocation and Task Offloading in a MEC/NFV-enabled C-RAN Network

In this paper, we propose a novel resource management scheme that jointly allocates the transmission power and computational resources in a centralized radio access network architecture. The network comprises a set of computing nodes to which the requested tasks of different users are offloaded. The optimization problem takes the transmission, execution, and propagation delays of each task into account, with the aim to allocate the transmission power and computational resources such that the user's maximum tolerable latency is satisfied. Since the optimization problem is highly non-convex, we adopt the alternate search method (ASM) to divide it into smaller subproblems. A heuristic algorithm is proposed to jointly manage the allocated computational resources and placement of the tasks derived by ASM. We also propose an admission control mechanism for finding the set of tasks that can be served by the available resources. Furthermore, a disjoint method that separately allocates the transmission power and the computational resources is proposed as the baseline of comparison. The optimal solution of the optimization problem is also derived based on exhaustive search over offloading decisions and utilizing Karush-Kuhn-Tucker optimality conditions. The simulation results show that the joint method outperforms the disjoint task offloading and power allocation. Moreover, simulations show that the performance of the proposed method is almost equal to that of the optimal solution.