## The Annals of Applied Probability

### Justifying diffusion approximations for multiclass queueing networks under a moment condition

#### Abstract

Multiclass queueing networks (MQN) are, in general, difficult objects to study analytically. The diffusion approximation refers to using the stationary distribution of the diffusion limit as an approximation of the diffusion-scaled process (say, the workload) in the original MQN. To validate such an approximation amounts to justifying the interchange of two limits, $t\to\infty$ and $k\to\infty$, with $t$ being the time index and $k$, the scaling parameter. Here, we show this interchange of limits is justified under a $p^{*}$th moment condition on the primitive data, the interarrival and service times; and we provide an explicit characterization of the required order ($p^{*}$), which depends naturally on the desired order of moment of the workload process.

#### Article information

Source
Ann. Appl. Probab., Volume 28, Number 6 (2018), 3652-3697.

Dates
Revised: January 2018
First available in Project Euclid: 8 October 2018

Permanent link to this document
https://projecteuclid.org/euclid.aoap/1538985632

Digital Object Identifier
doi:10.1214/18-AAP1401

Mathematical Reviews number (MathSciNet)
MR3861823

Zentralblatt MATH identifier
06994403

#### Citation

Ye, Heng-Qing; Yao, David D. Justifying diffusion approximations for multiclass queueing networks under a moment condition. Ann. Appl. Probab. 28 (2018), no. 6, 3652--3697. doi:10.1214/18-AAP1401. https://projecteuclid.org/euclid.aoap/1538985632

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