On Flow Reliability in Energy Harvesting Wireless Sensor Networks

A basic wireless sensor networks (WSNs) reliability problem calls for finding the likelihood that a sink node receives at least a certain amount of traffic generated periodically by sensor nodes that can either operate or fail. When the nodes rely on harvesting energy from the ambient environment, a node can be in any one of a possible number of energy states with probabilities that can be estimated using measured environmental data. A node's energy management unit can work by controlling the amount of data that can be periodically transmitted in each state. In this context, we formalize a flow reliability problem (denoted FLOWREL) in EH-WSNs. We present a method for computing lower bounds on exact solutions using an iterative algorithmic framework. Numerical results are presented to examine the performance of the devised methodology. Further, we discuss its use in a sample application that asks for determining the best sink location among a set of candidate locations.