Delay analysis of timed-token protocol and its application to a hybrid switching system

It is shown that the exact delay expression of the exhaustive service system can be used directly to derive a simple approximate expression for the average packet delay of the timed-token protocol. Simulation results show that this expression provides good estimates for the average packet delay when the ring latency is small relative to packet transmission time (in the case of low-capacity networks) and that its accuracy deteriorates as the ring latency increases (in the case of high-capacity networks). An approximate analytic method is developed that significantly improves the accuracy of the approximate expression and makes it insensitive to ring latency, and packet transmission time. The analytic method is successfully used to evaluate the average data packet delay of a hybrid-switching system in which the frame structure of FDDI II is used to support voice and data traffic