A simulation model for analyzing the performance behavior of token-ring local area networks

This paper describes the design and capabilities of a simulation program that models the behavior of a token-ring access local area network (LAN). Such networks consist of a variety of devices connected to a high speed transmission medium having a geographic extent limited to a few kilometers. Topologically, the transmission medium and devices constitute a closed loop or ring. Devices transmit messages on the ring only after obtaining control of a permission token that regulates access to the transmission medium. Attention is focused on the token-ring access protocol since the available evidence (see [1] and [2] for example) suggests that this protocol results in small delays at light workloads and controlled delay at heavy workloads. Based on this favorable assessment of performance, the token-ring access protocol is expected to be widely used in the future.