Scheduling transmissions in time-critical distributed systems

For a distributed system in factory automation featuring periodic processes with stringent time constraints, off-line scheduling is necessary, as it can guarantee that all the information produced will be delivered on time. As the size of the produced scheduling tables recording the transmission sequences can be very large, in this paper we dealt with the problem of reducing these tables, still maintaining a correct scheduling. The cost of this compression is a waste of bandwidth which will affect the acyclic traffic which is always present in addition to the cyclic traffic. The authors evaluate the influence of this bandwidth degradation of the system performances