There exist various service systems that have hierarchical structure. In hierarchical service networks, facilities at different levels provide different types of services. For example, in health care systems, general centers provide low-level services such as primary health care services, while the specialized hospitals provide high-level services. Because of demand congestion in service networ...

Queueing networks are important models of complex systems, such as packet routing networks, manufacturing systems, and time shared computer systems. In this paper, we investigate the question of stability of multiclass queueing networks within the adversarial queueing theory model, where workload is induced by an adversary. Prior work in the adversarial model considers only a special case of qu...

Queueing Networks are a widely used performance modeling tool that has been successfully applied to evaluate many kind of systems. In this paper we describe the queueing package, a collection of numerical solution algorithms for Queueing Networks and Markov chains written in GNU Octave (an interpreted language for numerical computations). The queueing package allows users to compute steady-stat...

The product form results recently published for Stochastic Petri Nets are combined with the well known product form results for Queueing Networks in the model formalism of Queueing Petri Nets yielding the class of product form Queueing Petri Nets. This model class includes Stochastic Petri Nets with product form solution and BCMP Queueing Networks as special cases. We introduce an arrival theor...

This paper describes the MQNA Markovian Queueing Networks Analyser, a software tool to model and obtain the stationary solution of a large class of Queueing Networks. MQNA can directly solve open and closed product-form queueing networks using classical algorithms. For finite capacity queueing models, MQNA generates Markovian description in the Stochastic Automata Networks (SAN) and Stochastic ...

The classical Erlang and Engset loss models have been used extensively in the traffic engineering of traditional telephone exchanges. More recently, these models have been generalized to the so-called loss networks, which provide models for resource sharing in multiservice telecommunication networks. In this paper, we introduce a new generalized class of models, queueing-loss networks, which ca...

The theory of queueing systems is traditionally considered as a branch of applied probability. Hence the toolkit used in the analysis of queueing system draws heavily on the theory of stochastic processes. Many problems in the area of queueing networks, however, are of algorithmic nature, and thus require algorithmic/complexity theoretic approaches. In this tutorial we will discuss several such...