A Sensor Web Middleware with Stateful Services for Heterogeneous Sensor Networks

As sensor networks become more pervasive there emerges a need for interfacing applications to perform common operations and transformations on sensor data. Web Services provide an interoperable and platform independent solution to these needs. A key challenge of using Web Services in this context is how to support ongoing sensor queries that persist over an extended period of time. In this paper we introduce Web Service Resource Framework (WSRF) mechanisms into the core services implementation of the NICTA Open Sensor Web Architecture (NOSA). NOSA is a suite of middleware services for sensor network applications which are built upon the OpenGIS Consortium´s Sensor Web Enablement standard. WSRF expands the functionality of our services to handle simultaneous observational queries to heterogeneous Sensor Networks. It facilitates the adoption of a multi-user, multi-threaded service environment. Using components from the Globus Middleware platform, NOSA takes a major step forward to achieving the vision of a Sensor Grid.