Situation modelling, representation, and querying in context-as-a-service IoT platform

As the Internet of Things (IoT) is entering the System-of-Systems phase, the demand for effortless access to contextual information will be a fundamental factor for IoT expansion, sustainability, interoperability and acceptance. A number of context management platforms are competing in the area, while the standardization efforts on the interfaces are still in the early stage. In this paper, we extend our previous work on the Context-as-a-Service platform and its interface-Context Definition and Query Language (CDQL). We propose a generic approach to represent and query situations in IoT environment. Moreover, we show how the temporal relations between situations can be used in situation descriptions and queries to define highlevel situations.