Dynamic Reconfiguration of Wireless Sensor Networks to Support Heterogeneous Applications

As larger numbers of Wireless Sensor Network (WSN) applications get deployed in our homes and offices, it is desirable to use the same network to run different applications. We present and analyze the problem of scheduling and supporting the execution of multiple heterogeneous applications on top of the same WSN. First, we establish that using the same MAC or network protocol is not sufficient to obtain acceptable performance across a set of applications that require different types of communication services from the protocol stack (e.g., low-rate reliable many-to-one collection vs point-to-point low-latency bulk-data streaming). Hence, we propose a framework to dynamically reconfigure the WSN and adapt its power consumption, transmission reliability, and data throughput to the different requirements of the applications. The framework makes it possible to specify, at design time, distinct network, MAC and radio protocols for each application as well as the events and policies triggering the WSN reconfigurations. At run-time, the WSN automatically reconfigures itself in response to these events and according to these policies. Through experiments on a 119-node testbed, we show that the proposed approach can reconfigure the whole network in few hundreds of milliseconds while incurring little memory and control overhead.