On the use of extents in distributed multimedia computing environments

In this paper a concept is proposed which summarizes both navigation- and query-based retrieval techniques of distributed information systems such as WorldWideWeb or the Wide Area Information System. It is argued that both access strategies are specific forms of content based retrieval. Based on an extension of the "anchor"-concept of hypermedia, the modeling primitive extent is introduced, whose purpose is to support both retrieval mechanisms. It is then shown, how this modeling primitive can be used to substantially enhance the throughput of a distributed multimedia information management system, based on the mechanism of server based extent computation.