Dipartimento di Ingegneria informatica, automatica e gestionale

This paper investigates various ways of minimizing energy consumption in Wireless Sensor Networks (WSNs). We are interested in those methods and technologies that allow network nodes to drastically decrease energy consumption by turning off their primary communication circuitry (main radio), arguably the main culprit of energy depletion. We consider WSNs whose nodes operate according to pre-set duty cycles and WSNs with nodes featuring very low-power wake-up radio devices. In these scenarios we evaluate the performance of an energy-aware routing protocol, showing that when nodes wake up their neighbors based on their suitability to forward data packets (semantic addressing), energy consumption and network lifetime are remarkably better than when all of a sender neighbors are awoken indistinctly (broadcast addressing) and than when nodes duty cycle. Protocols using semantic addressing achieve network lifetimes that are 10x higher than when broadcast addressing is used and three orders of magnitude better than in duty cycle-based networks. We also observe that semantic addressing keeps data latency at bay, achieving end-to-end latency similar to that in networks with nodes with the radio always on.