A Queueing Model for Token Rings with Priorities

Abstract

We present an analytic queueing model which predicts delays for priority traffic on token rings which use a reservation priority scheme (such as IEEE 802.5 and SAE AE-9B). Our model consists of live components: queueing delay, priority wait time, priority block time, transmission delay, and ring latency delay. We provide formulae and derivations for each. The model has been verified by comparison with a simulation of the IEEE 802.5 token ring. Although we model single-packet-per-token service, we show this to be operationally justified. Note: Abstract extracted from PDF file via OCR