Dependable Actuation in Wireless Sensor Networks

Our protocol uses a publish/subscribe approach to perform reliable actuation on a sensor network with changing topology. Selective actuation on a group of devices can be performed by publishing a message on a topic, and having the group subscribe to that topic. The message contains the data needed to perform the actuation. Our design reduces costly transmissions and uses a soft-state approach to cope with frequent topology changes. Its features and robustness are compared with those of epidemic protocols by means of simulation. Our protocol exhibits more efficient behavior when the actuation targets a selected group of devices within the sensor network; efficiency is similar in other cases. Furthermore, we provide feedback to the external actuating application. The robustness of our proposal is close to that of an epidemic model for moderate bit error rates.