Scalable and Efficient Tasking for Dynamic Sensor Networks

Sensor networks including opportunistic networks of sensor-equipped smart- phones as well as networks of embedded sensors can enable a wide range of applications including environmental monitoring,smart grids,intelligent trans- portation,and healthcare.In most real-world applications,to meet end-user requirements,the network operator needs to define and update the sensors’ tasks dynamically,such as updating the parameters for sensor data collection or updating the sensors’ code. Tasking sensor networks is necessary to reduce the effort in programming sensor networks.However,it is challenging due to dynamics and scale in terms of number of nodes,number of tasks,and sensing regions of the networks.In addition,tasking sensor networks must also be efficient in terms of bandwidth, latency,energy consumption,and memory usage. This dissertation identifies and addresses the problems of scalability and efficiency in tasking sensor networks.The first challenge in tasking sensor networks is to define a mechanism that represents multiple tasks and sensor groups efficiently taking into account the heterogeneity and mobility of sensors deployed over a large geographical region.Another challenge in tasking sensor networks in general,and embedded sensor networks in particular,is to design protocols that can not only efficiently disseminate tasks but also maintain a consistent view of the task to be performed among inherently unreliable and resource-limited sensors.