Navigating Distributed Services

This thesis explores the impact of three current trends which, when taken together, arefundamentally changing the way in which the task of navigating virtual environmentsis accomplished. The first concerns the changeover from a situation in which all dataand functionality reside locally to the user, to a situation where they are distributedacross the Internet. The second trend is the shift from a virtual environment that solelyconsists of distributed documents to a virtual environment that consists of bothdistributed documents and distributed services. The third and final trend is theincreasing diversity of devices used to access information on the Internet.The focal point of the thesis is an initial exploration of the effects of the trends onusers as they navigate the virtual environment of distributed documents and services.To begin the thesis uses scenarios as a heuristic device to identify and analyse themain effects of the trends. This is followed by an exploration of theory of navigationInformation Spaces, which is in turn followed by an overview of theories, and the stateof the art in navigating distributed services. These explorations of both theory andpractice resulted in a large number of topics for further investigation.The thesis focuses upon three sub-topics. The first deals with the general differencesbetween navigating distributed documents and navigating distributed services. Thesecond deals with the applicability of a geographical metaphor for collections ofdistributed services. The third and final sub-topic tries to answer the question of thedifferent metadata requirements distributed services have when compared todistributed documents.A study is devised to test the validity of three hypotheses, but also to provide specificdetails about the differences in how users search for documents vs. services, and togive a detailed overview of the required metadata for services. The study includes thebuilding of prototypes that are evaluated by experts and tested by users.Together, the scenario design, the literature review, the building of the prototype, andexpert and user evaluations test the validity of the hypotheses, the results of which canbe used to improve the user experience of navigation distributed services. Furthermorethe results include both a fully functional platform for browsing services and a largenumber of services. Both can be used for further studies.