Hypermedia interoperability : navigating the information continuum
Open Hypermedia Systems are designed to allow links to be authored and followed on top of any media format. The link structures are held separately from the documents in a software component called a Link Server. As hypermedia has matured as a research topic attention has turned to standardising the way in which components talk to Link Servers in order to provide interoperability. The Open Hypermedia Systems Working Group took up this challenge and proposed an Open Hypermedia Protocol (OHP). However, the scope of this proposal proved to be too large and the protocol was divided into domain specific parts (Navigational, Spatial and Taxonomic Hypermedia), tackling each domain differently, but consistently. It is questionable whether this step was the correct one, as the domains share many similar features. In this thesis I present a detailed examination of the information spaces that the OHP was attempting to model (from all these considered hypertext domains), which incorporates notions of both behaviour and context. This examination looks at what it means to navigate around the many dimensions of information, across these domains, and reveals a cohesive and continuous structure that I call the Information Continuum. The Fundamental Open Hypermedia Model (FOHM) is presented, which is capable of representing the structures of this continuum in a consistent and meaningful way. FOHM is coupled with an agent infrastructure to produce an implementation that demonstrates the model being used for cross-domain interoperability.