SLIM: Service Location and Invocation Middleware for Mobile Wireless Sensor and Actuator Networks

One of the main obstacles to the adoption of Wireless Sensor Networks (WSNs) outside the research community is the lack of high level mechanisms to easily program them. This problem affects distributed applications in general, and it has been replied by the Software Engineering community, which recently embraced Service Oriented Programming (SOP) as a powerful abstraction to ease development of distributed applications in traditional networking scenarios. In this paper we move from these two observations to propose SLIM: a middleware to support service oriented programming in mobile Wireless Sensor and Actuator Networks (WSANs). The presence of actuators into the network and the capability of SLIM to support efficient multicast invocation within an advanced protocol explicitly tailored to mobile scenarios, makes it a good candidate to ease development of complex monitoring and controlling applications. In the paper we describe SLIM in details and show how its performance easily exceeds those obtainable by using traditional approaches to service invocation in mobile ad-hoc networks.