A note on the sensitivity analysis for stationary and ergodic queues

Starting with some mild assumptions on the parametrization of the service process, per-turbation analysis (PA) estimates are obtained for stationary and ergodic single server queues. Besides relaxing the stochastic assumptions, our approach solves some problems associated with the traditional regenerative approach taken in most of the previous work in this area. First, it avoids problems caused by perturbations interfering with the regenerative structure of the sys-tem. Second, given that the major interest is in steady-state performance measures, it examines directly the stationary version of the system, instead of considering performance measures ex-pressed as Cesaro limits. Finally, it provides new estimators for general (possibly discontinuous) functions of the workload and other steady-state quantities