Waiting times in queueing networks with a single shared server

TL;DR

This paper introduces a new method to derive exact waiting-time distributions in complex queueing networks with a single shared server, accommodating internal routing that disrupts traditional Poisson assumptions.

Contribution

The paper develops a novel analytical approach to obtain exact waiting-time distributions in general queueing networks with internal routing, surpassing limitations of existing methods.

Findings

Derived explicit Laplace-Stieltjes transforms for waiting times.

Applicable to a wide range of queueing models with internal routing.

Enables analysis of models previously lacking waiting-time solutions.

Abstract

We study a queueing network with a single shared server that serves the queues in a cyclic order. External customers arrive at the queues according to independent Poisson processes. After completing service, a customer either leaves the system or is routed to another queue. This model is very generic and finds many applications in computer systems, communication networks, manufacturing systems, and robotics. Special cases of the introduced network include well-known polling models, tandem queues, systems with a waiting room, multi-stage models with parallel queues, and many others. A complicating factor of this model is that the internally rerouted customers do not arrive at the various queues according to a Poisson process, causing standard techniques to find waiting-time distributions to fail. In this paper we develop a new method to obtain exact expressions for the Laplace-Stieltjes transforms of the steady-state waiting-time distributions. This method can be applied to a wide variety of models which lacked an analysis of the waiting-time distribution until now.