A Middleware for Providing Efficient Real-time services in Sensor Networks
一种保证传感器网络实时服务的中间件机制

With the continuing advances in sensor networks and application design, appropriate middleware is needed to provide efficient QoS for coordinate concurrent applications on the sensor networks according the amount of resources and sensor energy. Usually, it is required that an instance of real-time application in sensor networks is periodically activated and must be completed before the next application instance is activated, and this results in data lost while acquiring rate is fast. In the paper, we first propose an event-triggered middleware framework and an executing model of real-time applications in sensor networks. And then, by using the timestamp of collection data to educe the timestamp of coordinate concurrent tasks and integrating application knowledge to tailor the design and implement of the middleware, an implement technique based on timestamp-reliance is presented to providing efficient data services and real-time response while guaranteeing time consistency and correctness of concurrent applications. Finally, we design an effective scheduling algorithms based on the model. Simulation test results show that by using the algorithms, the efficiency of data stream processing and real-time response can be enhanced, and the technique is suitable to process intermittent and high speed acquisition data in sensor networks.