Scheduled and nonscheduled access in a distributed system based upon a functional communication model

Request-response communication is studied in the framework of the functional communication model. A scheme that uses the channel access algorithm for distributed scheduling is investigated. A timed token protocol is used to control the two access modes, the scheduled access, with communication initiated by a server, and the nonscheduled access when a client sends a request to a functional group without prior consent from any of the servers in the group. In case of scheduled communication, the server guarantees the acceptance of the request