REALFLOW: Reliable Real-Time Flooding-Based Routing Protocol for Industrial Wireless Sensor Networks

Wireless technologies have been increasingly applied in industrial automation systems due to flexible installation, mobility, and cost reduction. Unlike traditional wireless sensor networks (WSNs), industrial wireless sensor networks (IWSNs), when expanding from wireless monitoring to wireless control, have more stringent requirements on reliability, real-time performance, and robustness in a number of industrial applications. Successive transmission failures or deadline misses in these applications may severely degrade the control quality and result in serious economic losses and safety problems. Therefore, when deploying IWSNs in harsh industrial environments, to achieve reliable and deterministic end-to-end transmissions is critically important. In this paper, we explain the primary challenges of designing appropriate routing protocols and present a reliable real-time flooding-based routing protocol for IWSNs (REALFLOW). Instead of traditional routing tables, related node lists are generated in a simple distributed manner, serving for packet forwarding. A controlled flooding mechanism is applied to improve both reliability and real-time performance. A seamless transition in the event of topology change can be achieved by REALFLOW. Performance evaluations via simulations verify that significant improvements of reliability, real-time performance, and network recovery time can be achieved by REALFLOW, compared with traditional routing protocols.