Query Routing in Wireless Sensor Networks: A Novel Application of Social Query Models

The Social Query Model (SQM) has been proposed in the literature for distributed search and routing over social networks. In this paper, we adapt SQM and the associated distributed query routing algorithm to a novel application domain – wireless sensor networks (WSNs). WSNs are nowadays routinely used for measuring various ambient properties (e.g., temperature, pressure) in uncontrolled environmental conditions (e.g., earthquake zone, flood area). The goal of the WSN in these cases is gathering information under potentially adverse situations and responding to queries from a base station reliably. The ability to work successfully in the wild necessitates that the query routing protocol in WSNs have certain properties, e.g., tolerance to node faults, ability to conserve battery life of sensor nodes, seamlessly handling nodes being added to or removed from the network, etc. We show how SQM satisfies all these desirable criteria, and validate the effectiveness of SQM-based routing by experiments on WSNs with different network configurations. Our results show that the SQM-based query routing algorithm outperforms popularity-driven degree-based routing algorithms, while providing useful performance guarantees.