In work package 5 a Sensor and Spatial Data Infrastructure (SSDI) is developed, which facilitates the information exchange between sensors, models, simulations, external data sources and the user through a GeoPortal in real-time.
The targeted SSDI serves as an interface between existing spatial-temporal data and real-time measurements using geo sensor networks (GSN). The data fusion with various external sources such as the “Marine Data Infrastructure Germany” (MDI-DE) is crucial for a holistic monitoring of dikes as only then the validity of the models and simulations can be ensured. Simultaneously, the computed simulation results obtained by the other work packages must be integrated in the SSDI via software interfaces in a sophisticated way.
The implementation of the SSDI follows the pattern of service-oriented architectures (SOA). Web services will be developed that open up access to data, models and simulations for the end user. International geo information standards of the INSPIRE initiative of the EU and the Open Geospatial Consortium (OGC) will be used to ensure interoperability. In addition to data models, these standards also include services for accessing geo data such as Web Map Service (WMS) and Web Feature Service (WFS), but also Web Processing Service (WPS). Furthermore, newly developed mechanisms and s-ervices are investigated, which obtain, analyze and process geo data streams in real-time. Hereby, sensor data and real-time simulations can be connected and integrated. Lightweight data exchange protocols such as the Internet-of-Things (IoT) protocol MQTT are one significant building block of this architecture. They can be used to enable lightweight messaging between the different subsystems.
For this purpose a so-called event bus will be introduced in the architecture which combines a data exchange and a notification mechanism. This centerpiece will be implemented using GeoMQTT, an extension to the MQTT protocol. These mechanisms provide powerful functionalities such as the invocation of arbitrary process chains operating on geo data streams. For instance, newly measured sensor data can be pushed forward to post processing services to e.g. filter out outliers or noise before they are stored persistently.
The central access point will be a web-based dike geo portal which provides access to both real-time sensor data and 3rd party data using stationary and mobile devices (e.g. smartphones). In addition, the results of the hydraulic-engineering analysis and simulation tools, as well as notification and alert functionalities will be integrated.