Fast Release/Capture Sampling in Large-Scale Sensor Networks

Efficient estimation of global information is a common requirement for many wireless sensor network applications. Examples include counting the number of nodes alive in the network and measuring the scale of physically correlated events. These tasks must be accomplished at extremely low overhead due to the severe resource limitation of sensor nodes, which poses a challenge for large-scale sensor networks. In this paper, we develop a novel protocol FLAKE to efficiently and accurately estimate the global information of large-scale sensor networks based on the sparse sampling theory. Specially, FLAKE disseminates a small number of messages called seeds to the network and issues a query about which nodes receive a seed. The number of nodes that have the information of interest can be estimated by counting the seeds disseminated, the nodes queried, and the nodes that receive a seed. FLAKE can be easily implemented in a distributed manner due to its simplicity. Moreover, desirable tradeoffs can be achieved between the accuracy of estimation and the system overhead. Our simulations show that FLAKE significantly outperforms several existing schemes on accuracy, delay, and message overhead.