DeCoT: A Dependable Concurrent Transmission-Based Protocol for Wireless Sensor Networks

Concurrent transmission (CT)-based wireless sensor networks, where nodes transmit at the same moment upon receiving successfully, begin to be applied to real-world scenarios. CT-based protocols have been proven experimentally that they can achieve good the end-to-end performance, namely high reliability, low latency, and high energy efficiency. For various communication patterns (one-to-many, many-to-one, and many-to-many), most current CT-based networks require a given and fixed host to realize global synchronization and scheduling. However, in real-world cases, there is a great deal of interference in the 2.4 GHz ISM band. Interference can partition the network unexpectedly due to the centralized scheduling in current CT-based networks. Even worse, current CT-based networks cannot complete the initialization phase if the unexpected partition occurs at an very beginning. To address this problem, we propose a dependable CT-based protocol (DeCoT) for wireless sensor network (WSN) to support information exchange under adverse conditions. In DeCoT, continuous transmission with a channel hopping mechanism maintains links under interference and an initiated mechanism decentralizes the network. Through our experiments in FlockLab, under interference, DeCoT achieves an average reliability of 87%, and outperforms the state-of-the-art flooding protocol, namely Robust Flooding that won the 1st place in the EWSN 2017 Dependability Competition. Especially when the source nodes are placed sparsely, DeCoT speeds up the information exchange. Above all, DeCoT can complete the initialization and work properly even when the network partitions unexpectedly. DeCoT has been evaluated as the most reliable protocol in the EWSN 2018 Dependability Competition with respect to resistance against interference. Thus, DeCoT can function dependably under interference.