Context source selection for federated context management in ubiquitous computing environment

Abstract

Recently, the scope of context management is being extended from a single domain to multiple domains, as the ubiquitous computing services become more and more sophisticated. A user context is identified not only within a domain where the user physically belongs, but also across multiple domains he or she is associated with. In this thesis, we propose a federated architecture consisting of a global context manager (CM) and several local CMs for federated context managements. Since in multi-domain there will be multiple context sources which provide the same type of contexts, in such federated operations the global context manager has to select a context source when the global context manager aggregates them into global context-finding process. This context source selection problem for a federated context processing is stated, and selection scheme has also been proposed in this thesis. We introduce a formal definition of duplicate context sources, and then propose a context source selection scheme. We also demonstrate how the selection scheme improves the results of context reasoning in federated context management.