An Energy-Efficient Hierarchical Topology Control Algorithm in Software-Defined Wireless Sensor Network

Software Defined Wireless Sensor Network (SD-WSN) is a new type of sensor network that combines SDN and WSN, which has rapidly emerged in recent years. However, the energy of nodes in SDWSN is still limited. Topology control is one of the important methods to solve this problem. Therefore, this paper proposes an energy-efficient hierarchical topology control (EEHTC) algorithm. The proposed EEHTC algorithm includes two parts: lower-layer topology control (LTC) for common sensor nodes (CSNs) and upper-layer topology control (UTC) for software-defined sensor nodes (SSNs). The LTC algorithm considers the transmission distance, the number of nodes in the cluster and the residual energy of the selected relay node as clustering factors, selecting the most suitable SSN as the cluster head for information transfer. When the SSN forwards data, the node will exhibit selfish behavior in generating topology to save energy. Therefore, the UTC algorithm considers the SSN load and transmission energy consumption to generate the topology by using the network formation game. The simulation results show that compared with the existing algorithms, EEHTC algorithm can effectively extend the network lifetime and reduce energy consumption of the node.