Mmdd { a Distributed Meta-media Simulation Framework

We describe an experimental system supporting the creation of highly interactive simulations which are rich in media and structure. Strengths include author-modiiable schema, author-reconngurable front ends, and relatively straightforward extensibility to new media types and search methods. The framework of meta-media distributed databases (MMDD) manages associations of arbitrary renderable objects (such as structured text, 3D-graphics, musical scoreeles, video, certain exe-cutables) using a hybrid object-oriented, relational database abstraction. Key features of the architecture include (1) atoms that are not traditional documents but abstract entities, which endows the MMDD with unusual exibility, and (2) object-oriented core mediating classes which provide rational, extensible meta-data-and content-based services. The MMDD was designed around the projected needs of faculty and their assistant authors, based on extensive experience with creating multimedia simulations. It currently supports several distributed media testbeds in the elds of drama, history, music, foreign languages , and art.