Cabot: On the Ontology for the Middleware Support of Context-Aware Pervasive Applications

Middleware support is a major topic in pervasive computing. Existing studies mainly address the issues in the organization of and the collaboration amongst devices and services, but pay little attention to the design support of context-aware pervasive applications. Most of these applications are required to be adaptable to dynamic environments and self-managed. However, most context-aware pervasive applications nowadays have to carry out tedious tasks of gathering, classifying and processing messy context information due to lack of the necessary middleware support. To address this problem, we propose a novel approach based on ontology technology, and apply it in our Cabot project. Our approach defines a context ontology catered for the pervasive computing environment. The ontology acts as the context information agreement amongst all computing components to support applications with flexible context gathering and classifying capabilities. This allows a domain ontology data-base to be constructed for storing the semantics relationship of concepts used in the pervasive computing environment. The ontology database supports applications with rich context processing capabilities. With the aid of ontology technology, Cabot further helps alleviate the impact of the naming problem, and support advanced user space switching. A case study is given to show how Cabot assists developers in designing context-aware pervasive applications.