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the transmission of periodic message streams. Moreover, by setting an adequate relative phasing between message streams, designers can control the collisions at medium-access level, eliminating, or bounding, networkinduced mutual interference. This feature leads to composability with respect to the temporal behavior because elimination of mutual interference allows the temporal behavior of a subsystem when isolated, to remain unaffected upon integration in the global distributed system. Relative phasing control also provides improved temporal behavior under heavy traffic conditions. The feature enables better packing of transmissions in the communication system. This means shorter worstcase response times to communication requests and more efficient bandwidth utilization. Finally, the time-triggered paradigm supports detection of connectivity failures at the receiver because message-arrival times are known across the system. Despite these positive properties, the timetriggered paradigm also has a downside: It is inefficient concerning average network utilization when one or more nodes generate messages in a sporadic way and require fast response. For example, with alarms, eventtriggered communication is more efficient because senders transmit only in response to significant state changes, that is, events. Of course, the event-triggered paradigm also has a downside. It does not support composability with respect to the temporal behavior because the asynchrony of node transmissions leads to mutual interference whenever nodes are integrated in the system. In addition, the requirements for worst-case communication can …