An approximate method for the performance analysis of PLAYTHROUGH rings

Analytical models are presented and shown to approximate adequately simulation results for average message queuing time, service time, and control frame round trip time on ring-topology local area networks. These LANs use a PLAYTHROUGH protocol, a data link layer medium access control protocol that achieves concurrent transfer of multiple messages of arbitrary length. The analytical predictions of data message service time and control frame round trip time are used in a queuing system model of average message waiting times versus throughput for this class of multiserver circuit-switched ring under assumptions of uniform and symmetric traffic and a shortest outbound distance first service discipline at each node. The analytical models are validated using simulation results. The analysis includes both the effects of competing traffic originating at other nodes on the ring and the effects of the medium access control mechanism overhead on the waiting times experienced by messages arriving at an arbitrarily chosen node