Standardizing headers in the quest for interoperability

The popular, business, and scientific media are full of predictions and promises for the national and global information infrastructures. However, one key problem is enabling interoperability in an open communications environment. In digital communications, simple examination does not reveal what a stream of bits represents-"bits are bits". Headers and descriptors, a labeling mechanism, provide important identification for bit streams and thereby enable interoperability. Our work on headers and descriptors is part of a continuing effort to understand and foster the convergence and interplay of computing, communications, and interactive media. The header/descriptor concept, as represented here, began with US based efforts to define an advanced television system, high definition television (HDTV). Cross industry harmonization objectives, especially interoperability with digital computer and telecommunications systems, became formal selection criteria for the Federal Communications Commission's advanced television selection process. We explain the objectives and rationale underlying our work on headers and descriptors, and propose specific design concepts for achieving a truly universal header. An attractive, accessible, and sustainable information infrastructure depends on easy data sharing and preservation across varying systems. This larger goal, not simply the market needs of advanced television, drives our efforts.