Effect of nodes reordering on the schedulability of real-time messages in timed token networks

This letter addresses the effect of different ordering patterns of network nodes on the ability to schedule real-time messages in a timed token network where the timed token medium access control protocol is employed. It is found that for any given setting of network parameters, a set of real-time message streams which is unschedulable under one particular nodes-ordering may become schedulable under another different nodes-ordering. Some guidelines for avoiding a possible misjudgement in the schedulability due to inappropriately ordered nodes are discussed.