Efficient route update and maintenance processes for multipath routing in large-scale industrial wireless sensor networks

Communication reliability is one of the major concerns in wireless sensor networks (WSNs). Multipath routing is an effective way to improve communication reliability in WSNs. However, most of existing multipath routing protocols for sensor networks are reactive and require dynamic route discovery. If there are many sensor nodes from a source to a destination, the route discovery process will create a long end-to-end transmission delay, which causes difficulties in some time-critical applications. To overcome this difficulty, efficient route update and maintenance processes are proposed in this paper. They limit the amount of routing overhead with a two-tier routing architecture, and use combined piggyback and trigger updates instead of periodic update, which is the main source of unnecessary routing overhead. Simulations are carried out to demonstrate the effectiveness of the proposed processes in reducing routing overhead over existing popular routing protocols.