Abstract

Sensor networks are being increasingly deployed for diverse monitoring applications. Event data are collected at various sensors and sent to selected storage nodes for further in-network processing. Since sensor nodes have strong constraints on their energy usage, this data transfer needs to be energy-efficient to maximize network lifetime. In this paper, we propose a novel methodology for trading energy versus latency in sensor database systems. We propose a new protocol that carefully schedules message transmissions so as to avoid collisions at the MAC layer. Since all nodes adhere to the schedule, their radios can be off most of the time and they only wake up during welldefined time intervals. We show how routing protocols can be optimized to interact symbiotically with the scheduling decisions, resulting in significant energy savings at the cost of higher latency. We demonstrate the effectiveness of our approach by means of a thorough simulation study.

Citations