Mean cyclic period of polling model with double classes of objects in each queue

To evaluate time-token based network protocol, such as FF and Profibus, a new polling model, PMDC is investigated. Firstly, PMDC (in this paper, the two classes of object within each queue is deserved gated service and limited service respectively) is described normally. Secondly, the embedded Markov chain of object waiting queue length under stable condition is constructed. Then mean cyclic period under system equilibrium is deduced by means of generating function and Laplace-Stieltjes Transform, and the result is is emended after the effect of part or all unstable limited queues being considered. At last, analytical is validated by numerical simulation.