Database Systems: Design of a Prototype Videotex System

This paper describes a prototype interactive videotex system built for a concept trial in which home and small business users would access a variety of services based on existing white- and yellow-page Listing services using a modified television equipped with a full alphanumeric keyboard. As the term interactive videotex connotes, the user would have available a two-way information-delivery system providing selective access to electronic information transmitted over telephone lines from a computer system. The concept trial, and the system supporting it, would provide an experimental test-bed for determining user reaction to the medium and to the services provided in that medium. Independent waves of users would have access to the system over the trial period, and services offered could be added, modified, or removed from wave to wave based on user feedback in preceding waves. The system design for the prototype had to accommodate several requirements: (i) The system must be flexible to provide for growth in the services offered over the trial period. This growth could include the addition of new services with significantly different functional requirements, including transaction services utilizing database-management capabili2475