Timeout control for data aggregation in sensor networks with packet size limit

In-network data aggregation is one of the key technologies in wireless sensor networks. Because data aggregation inherently incurs a tradeoff between energy efficiency and delivery delay, several solutions have been proposed to control the waiting time before transmission of an aggregated data (i.e. data aggregation timeout). In this work we consider the case when one packet can carry multiple sensing data elements and this aggregation is limited to a finite number due to the limitation of packet size. Based on the idea that the timeout may be determined by the current number of waiting data elements, we propose a scheme for varying timeout, analyze its performance using a stochastic model, and show how to customize the varying timeout in the proposed scheme for energy efficiency or low delay. Experiment results show that our analytical model accords well with the real world implementation and our scheme facilitates efficient tradeoff between energy and delay, that is, high energy efficiency can be achieved with little overhead in delay, and vice versa.