Traffic Load Minimization in Software Defined Wireless Sensor Networks

The emerging software defined networking enables the separation of control plane and data plane and saves the resource consumption of the network. Breakthrough in this area has opened up a new dimension to the design of software defined method in wireless sensor networks (WSNs). However, the limited routing strategy in software defined WSNs (SDWSNs) imposes a great challenge in achieving the minimum traffic load. In this paper, we propose a flow splitting optimization (FSO) algorithm for solving the problem of traffic load minimization (TLM) in SDWSNs by considering the selection of optimal relay sensor node and the transmission of optimal splitting flow. To this end, we first establish the model of different packet types and describe the TLM problem. We then formulate the TLM problem into an optimization problem which is constrained by the load of sensor nodes and the packet similarity between different sensor nodes. Afterwards, we present a Levenberg-Marquardt algorithm for solving the optimization problem of traffic load. We also provide the convergence analysis of the Levenberg-Marquardt algorithm. Finally, we implement the FSO algorithm in the NS-2 simulator and give extensive simulation results to verify the efficiency of FSO algorithm in SDWSNs.