Providing energy conservation together with the Quality of Service (QoS) become more challenging in Wireless Mesh Networks (WMNs). A promising way to achieve this goal is to design a routing mechanism that takes both energy and QoS into account. On the other hand, Software Defined Networking (SDN) is an emerging network paradigm which separates the control plane from the data plane and facilitates a high level of programmability and manageability. In this paper, we propose FACOR, a novel SDN-based routing mechanism which aims at minimizing the energy consumption while providing a certain level of QoS for multimedia applications in wireless mesh networks. This technique is essentially suitable for battery-operated mesh nodes with solar panels. To obtain optimal paths, FACOR first estimates the cost of each network link using a fuzzy logic system. The fuzzy part takes parameters related to the quality of service and the energy in order to calculate the cost of the links. The routing problem is then formulated as an Integer Linear Programming (ILP) model. Since ILP is NP-complete, we propose an Ant Colony Optimization (ACO)-based algorithm to solve the model. The proposed method is implemented in the well-known OpenDayLight controller and strictly follows a modular design for the sake of efficiency. Simulation results confirm the effectiveness of our mechanism which achieves a gain of about 17% and 10% in terms of network lifetime and PSNR, respectively, compared to other methods.
