“…An important feature of the newly developed technique is that it can be applied to a myriad of models which lacked an analysis of the waiting-time distribution until now. One could apply the framework (possibly after some minor modifications) to obtain distributional results in all of the aforementioned special cases of the studied system [1,9,19,23,30,31,32,33,34] but also, for example, in a closed network [2], in an M/G/1 queue with permanent and transient customers [8], in a network with permanent and transient customers [3], or in a polling model with arrival rates that depend on the location of the server [4,7]. Although we study a continuous-time cyclic system with gated or exhaustive service in each queue, we may extend all results -without complicating the analysis -to discrete time, to periodic polling, to batch arrivals, or to systems with different branching-type service disciplines such as globally gated service.…”