ABSTRACT
We have formulated the data collection process within wireless sensor networks as a scheduling problem to alleviate workload on the data collection centers. A sensor device has three tasks: sensing data, processing data, and transmitting the collected data. We modeled the sensor’s three tasks as a task-flow graph (TFG), and then we combined all TFGs for all sensors within the Wireless Sensor Network (WSN) as a super task-flow graph (STFG). We utilized two scheduling algorithms, as soon as possible (ASAP) and as late as possible (ALAP), to order all tasks within the STFG subject to the data collection centers’ limitations. The experimental results provide excellent boundaries on how early and how late to schedule all sensors’ tasks with the variation of the number of data collection centers.
