In this paper, we present a complete IoT (Internet of Things) system, starting from a network of smart sensors and actuators named OCARI to applications ready to use such as the KASEM predictive maintenance system or DISPLAY, a simple web application for consulting sensors results. To ensure interoperability and a high level of standardization, a customized but compatible OPC UA industrial middleware implementation, named OPC UA / ROSA, allows secured communications. It also acts as a distributed contextual services discovery mechanism.
Industry 4.0 paradigm is the next industrial revolution in which smart sensors and actuators with wireless connectivity capability will deeply change the way industrial installations work. Process monitoring will be more smart and predictive thanks to low cost and reliable measurement capability that can be quickly implemented and deployed. Contextual services may then be easily implemented using the information enriched by pervasive sensors. In this scenario, implementing a suitable middleware that helps to securely orchestrate the information flow is essential.