Consensus-based decentralized resource sharing between co-located Wireless Sensor Networks

With the emergence of various co-located Wireless Sensor Networks (WSNs) in applications such as smart buildings and smart cities, it becomes increasingly important to facilitate their interaction. The aim of inter-network collaboration is to leverage the performance of each WSN, as well as the quality of service of the overall system. In this paper, we propose a decentralized method for inter-network collaboration, where each node is able to initiate a consensus-reaching procedure among the nodes from its network and terminate it after the consensus is reached. After that, it exchanges the information with a node from a neighboring network. In order not to interfere with the main task of the WSNs (detecting and reporting interesting events), our consensus algorithm needs to be energy-efficient and fast. We emphasize the importance of our approach on a case study of a smart surveillance application, where a gas WSN and video WSN share the same physical environment. The performance of the consensus algorithm during intranetwork communication (prior to inter-network communication) is experimentally investigated, using off-the-shelf wireless sensor platforms. We introduce an energy-time factor that indicates the optimal communication rate in terms of energy- and time-efficiency of the consensus algorithm. In our experiments, the best performance is achieved for period of communication 0.1 s (i.e., 2% duty cycle).