Reliable and Efficient Data Acquisition in Wireless Sensor Networks in the Presence of Transfaulty Nodes

A collection of spatially distributed sensor nodes in a wireless sensor network (WSN) work collaboratively to sense the physical phenomena around them and then send the sensed information to the sink node through single-hop or multihop paths. In this work, we propose a scheme, named ReDAST, for reliable and efficient data acquisition in a stationary WSN in the presence of transfaulty nodes. Due to the transfaulty behavior, a sensor node gets temporarily isolated from the network. Temporary node isolation leads to the formation of dynamic communication holes in the network, which form and disappear dynamically. Furthermore, they may increase or decrease in size dynamically as well. These effects result in loss of information in the radiation-affected area. To prevent information loss in WSN due to transfaulty behavior of sensor nodes, in the proposed scheme, we construct the network using sensor nodes having dual mode of communication-RF and acoustic. To get redundant coverage within a radiation affected area, all the sensor nodes in the area become activated and switch to the acoustic communication mode after detecting themselves to be affected by radiations. In-network data fusion is performed to get actual information from the redundant information received from the radiation-affected area. Simulation results exhibit that the proposed scheme, ReDAST, achieves better energy efficiency and reduced average end-to-end delay than sensor nodes having only acoustic mode of communication.