Semantic Registries for Heterogeneous Sensor Networks: Bridging the semantic gap for collaborative crises management

The management of heterogeneous sensor networks is a complex task. Moreover, such networks often form an isolated system that needs to be connected to other network systems. Therefore, a system-of-systems approach is required. A sensor registry is the central part of a distributed sensor network. In this paper, we describe how to enhance sensor registries with semantic technologies in order to overcome some of their limitations. The Sensor Web Enablement standards of the Open Geospatial Consortium constitute a consistent and flexible framework in order to assure syntactical interoperability between applications, which make abundant use of data from sensor networks operated by heterogeneous stakeholders. The data model used throughout these standards is the Observation & Measurement model. The conversion into an ontology provides an easier handling of the model. In this paper, we propose the use of such an ontology as the basis of a Semantic Registry. Besides providing the information about the available sensor infrastructure and their semantically rich annotations, it can easily be extended to handle for example information about available services for data analysis or simulations. Furthermore, the resilience of the SRs is a crucial point in the system architecture to prevent it becoming a single point of failure.