Providing reliable communications in a remotely monitored large-scale deployment of Wireless Sensor Networks is a challenging task. In this paper, we deal with such a deployment to monitor a landslide prone zone where the nodes sense geological attributes essential for early warning. The deployment area is a hilly mountain with different demographic characteristics. Establishing network connectivity in this deployment site for real-time streaming of sensor data involves dealing with site specific challenges such as asymmetric links, dynamic network conditions due to rough weather, inadequate solar power, network fail-over and re-connection problem etc. Our deployment makes use of only a few number of relay nodes for connecting the wireless sensor network to a field management center through an IoT gateway. The field management center makes use of multiple fault-tolerant WAN networks to relay the data to a remote central data management center for deep data analysis and for generating early warnings prior to a catastrophic event. This paper provides insights into our experiences from successful deployment of a WSN system and reports real-time measurements taken in the field for ensuring network reliability. Evaluation of our system reflects that the network is able to provide reliable communication by providing a fail-over for streaming data with less than a minute to re-establish the connection and the gateway software is capable of handling heterogeneous sensor readings at a rate up-to 1700/s within a latency of 10 s while delivering the data to the data center. The system also achieves highly accurate time synchronization in the order of microseconds throughout the network.
S. Kumar, Subhasri Duttagupta, Rangan, V. P., and Ramesh, M. Vinodini, “Reliable network connectivity in wireless sensor networks for remote monitoring of landslides”, Wireless Networks, vol. 26, no. 3, pp. 2137 - 2152, 2020.