SDN-Based Routing Mechanism for Industrial Wireless Sensor Networks

With the development of industrial network, Industrial Wireless Sensor Networks (IWSNs) outperform traditional wired automation system in terms of flexibility, scalability, and efficiency, etc. And IWSNs have critical demands on reliable and real-time data transmission. To meet these demands and enhance efficiency, a SDN-based routing mechanism for IWSNs is proposed in this paper, to determine the global optimal routing strategy based on the cognition of real-time network status. Firstly, a topology discovery algorithm based on multi-controller collaboration is proposed to improve the efficiency of the SDN controllers' cognition of network status, and each controller in the network can perceive the global network status by synchronizing information. Then, combined with the cognition of controllers for network status, a link quality-aware routing algorithm (LQAR) is proposed, further the global optimal routing is calculated and distributed to the field devices. Additionally, a node failure response strategy and a controller failure response strategy are proposed to enhance the reliability of the network. The simulation results show that the proposed routing mechanism can guarantee real-time data transmission and significantly improve the reliability compared with the traditional industrial wireless network routing mechanisms.