Dynamic power control and delay-aware forwarder selection in mostly-off WSNs

During the past decade, lifetime maximizing in wireless sensor networks was the major concern in this research area. Thus, “mostly-off” sensor nodes alternate between active and sleep states in many solutions nowadays. Unfortunately, these cycles involve strong sleep latencies which are the major limitation leading the solutions to suffer severe end-to-end delay degradation. Our objective in this paper is to investigate the delay issue in low duty-cycled WSN. We propose a delay-aware mechanism where each node having packets to send must choose a forwarder whose next active slot is the closest. Besides, we combine power controlled unicast transmissions with dynamic forwarder selection to better bound the communication delay and save energy. Through extensive simulations, we examine the performance of our design under different configurations and show how it outperforms the traditional routing schemes such as shortest-path algorithm.