Specification, design, and implementation of an interactive conferencing system

The specification, design and implementation of a text-based multiway interactive conferencing program are presented. The system is described in three parts: the user interface, the distribution mechanism for users´ contributions, and the floor control scheme. One specific system of floor control using the formal specification language Z is specified. The separation of the distributed operation of the exchange of speech in the conference from the floor control mechanism has led to the possibility of implementing an open floor conferencing system, and then adding floor control. The only operations necessary to add floor control are those required to allow or prevent use of a channel from each user to any other. The extra state incurred in the conference server processes is the 2-D matrix of user by user channels, with each entry showing allowed/disallowed