On the Stability of Communication Systems with Timed Token Protocols

Medium Access Control protocols for high speed LAN/MANs often employ a timer-controlled token passing mechanism to control station access to the shared media. These protocols support time-critical (real-time) applications, and provide priority among non time-critical applications. This paper considers the stability of systems with several target token rotation times. It shows that there do not exist simple, general stability bounds for these systems, because these bounds may depend on the arrival processes and the transmission time distributions not only through their means.