EDR: A Sink Failure Resilient Approach for WSNs

Data collection, redistribution and retrieval are essential components of monitoring wireless sensor networks (WSNs). In dense WSN deployments, generated and sensed data are usually sent to a sink that can be reached through one or multiple hops. In the case where communications with the sink are disrupted due to different reasons, the data must be stored in the network for later retrieval. When we consider in-network storage, we must redistribute the data among an energy-constrained network with sensors that have a low storage capacity. In this paper, we combine both data redistribution and retrieval into a single problem and propose an algorithm named EDR: energy-efficient data redistribution and retrieval. EDR is a distributed energy-efficient algorithm for in-network storage and later retrieval in WSNs. We analyze different scenarios including multiple data producers and multiple sinks. We formulate the problem as an optimization problem and use linear programming (LP) to find the optimal solution. We implemented our technique using real sensors to demonstrate the feasibility of our algorithm. We show that our approach is an energy-efficient solution for node selection when redistributing data in a WSN for eventual retrieval.