Multipath construction and management protocol for mobile sinks in wireless sensor networks

In Wireless Sensor Networks (WSNs), emergency applications such as fire alerts or intruder detections request to accomplish reliable data delivery on a path from a source to a mobile sink. For reliably delivering data to a mobile sink, many multipath and mobility supporting protocols were proposed. However, since they do not consider link qualities and energy state information to construct multipaths, they require frequent reconstructions of the multipaths due to link or node failures from poor links or energy depletions. Moreover, since they use continuous footprint-chaining or periodic global path reconstructions to support sink mobility, they cannot perfectly provide multipaths from a source to the mobile sink or can cause much energy consumption of sensor nodes to reconstruct multipaths globally. Thus, we propose a multipath routing protocol based on link quality and energy state information for mobile sinks in WSNs. The proposed protocol constructs multipaths consisting of sensor nodes with good link qualities and high energy states to reduce multipath reconstructions. The proposed protocol also uses a reverse path reconstruction and local modification scheme based on our analytical model to reconstruct multipaths energy-efficiently due to movements of a sink. Simulation results conducted in various environments show that the proposed protocol has better performance than the existing protocol.