Reliable actuation in sensor networks

Abstract

We present a protocol that uses a publish/subscribe approach to perform reliable but efficient actuation over a sensor network whose topology may change. Actuation on a given group of devices in the sensor network is achieved through a publish operation on the topic the devices in that group are subscribed to. The publication message contains the necessary data to successfully perform the actuation. We make the case for our design showing that: a) suitable data distribution techniques and cross-layer optimizations can reduce transmissions within the messaging layer of the sensor-network b) a soft-state approach can help with the frequent topology changes in wireless sensor networks caused by the transmission medium. We describe our protocol and compare its features and robustness to those of epidemic protocols through simulation. Our protocol is more efficient when the actuation is performed on selected groups of devices within the sensor network. In the general case, the efficiency of our proposal is similar to that of an epidemic model, plus feedback is given to the initiator of the actuation. Robustness remains close to the epidemic approach, even for moderate bit error rates. © 2007 ACADEMY PUBLISHER.