Analytic Models of Cyclic Service Systems and Their Application to Token-Passing Local Networks

Using the frameworK of cyclic-service systems with a single server, two different token-passing models are investigated. The first model is approximate, obtaining the free-taken's cycle-time distribution on an asymmetric system with infinite capacity buffers and single-token operation. The second model is exact. yielding the cycle-time distribution of the free-token on an asymmetric system with wtit-capacity buffers. and single-token operation. The latter result is verified using known results for symmetric, unit-capacity buffer systems. In order to demonsuate the positive effects of buffering, a small variation of the unit-capacity buffering scheme is introduced. Computational results include performance measures such as throughput, utilisation. loss probabilities, mean cycle-times. cycle-lime distributions and a comparison of two buffering schemes. • This research was supponcd by rho:. National So:.icncc FOUI'Idauon under gTalll ECS-83-04967.