An ontology-based negotiation protocol and context-level agreements

Abstract

Services and applications in pervasive environments must adapt to changes occurring in the surrounding environment and meet the needs of mobile users according to the users' changing situations. Existing context-aware architectures and middleware are faced with two problems. First, is their weakness in expressing complex inter-context relationships, stemming from use of less capable approaches to modeling contextual knowledge. Secondly, context dissemination methods used by these systems result in network flooding, unrestricted access to private context information, and the inability of consumers to limit or personalize received context. This thesis provides an ontology-based context-level negotiation protocol along with a context-aware system architecture. The protocol permits context consumers to personalize their received context information through negotiations with context providers. The thesis illustrates the use of this negotiation protocol through the design and implementation of a context-aware system architecture capable of acquiring, modeling, reasoning and disseminating context information through ontologies.