Delay-aware Routing in Low Duty-Cycle Wireless Sensor Networks

In low duty-cycle sensor networks, sensors sleep most of their time; it is consequently hard for sensors to maintain always-awake communication links. One major challenge is therefore to design communication algorithms to reduce the delivery delay. In this paper we propose and evaluate a delay-aware routing algorithm for low duty-cycle sensor networks. The proposed algorithm first organizes the network into a layered structure. And then the sensor with packets ready to be sent dynamically determines a forwarder from multiple potential next-hop sensors in terms of timeliness. Simulation results show that the proposed algorithm outperforms the static shortest-path routing in delivery delay and drop rate.