Class dependent departure process from multiclass phase queues: Exact and approximate analyses

In this paper we study class dependent departure processes from phase type queues. When the arrival process for a subset of the classes is a Poisson process, we determine the Laplace-Stieltjes transform of the stationary inter-departure times of the combined output of all the other classes. We also propose and test approximations for the squared coefficient of variation of the stationary inter-departure times of each customer class. The approximations are based on the detailed structure of the second order measures of the aggregate departure process. Finally, we propose renewal approximations for the class dependent departure process that take into account the utilization of the queue that customers next visit.

[1]  Ward Whitt Towards better multi-class parametric-decomposition approximations for open queueing networks , 1994, Ann. Oper. Res..

[2]  Frank Kelly,et al.  Reversibility and Stochastic Networks , 1979 .

[3]  W. Whitt Approximations for departure processes and queues in series , 1984 .

[4]  Ward Whitt,et al.  The Fourier-series method for inverting transforms of probability distributions , 1992, Queueing Syst. Theory Appl..

[5]  Susan L. Albin,et al.  Approximating a Point Process by a Renewal Process, II: Superposition Arrival Processes to Queues , 1984, Oper. Res..

[6]  Ward Whitt,et al.  Variability functions for parametric-decomposition approximations of queueing networks , 1995 .

[7]  Ward Whitt,et al.  Arranging Queues in Series: A Simulation Experiment , 1990 .

[8]  Gabriel R. Bitran,et al.  Analysis of the ΣPhi/Ph/1 Queue , 1994, Oper. Res..

[9]  Gagan L. Choudhury,et al.  Numerical Computation of the Moments of a Probability Distribution from its Transform , 1996, Oper. Res..

[10]  Wolfgang Fischer,et al.  The interdeparture-time distribution for each class in the ∑iMi/Gi/1 queue , 1989, Queueing Syst. Theory Appl..

[11]  David M. Lucantoni,et al.  New results for the single server queue with a batch Markovian arrival process , 1991 .

[12]  Richard Bellman,et al.  Introduction to Matrix Analysis , 1972 .

[13]  Ward Whitt,et al.  A Light-Traffic Approximation for Single-Class Departure Processes from Multi-Class Queues , 1988 .

[14]  Gabriel R. Bitran,et al.  Approximating Nonrenewal Processes by Markov Chains: Use of Super-Erlang (SE) Chains , 1993, Oper. Res..

[15]  Hisashi Kobayashi,et al.  Accuracy of the diffusion approximation for some queuing systems , 1974 .

[16]  Marcel F. Neuts,et al.  Structured Stochastic Matrices of M/G/1 Type and Their Applications , 1989 .

[17]  William L. Maxwell,et al.  Theory of scheduling , 1967 .