eprintid: 2583
rev_number: 7
eprint_status: archive
userid: 6
dir: disk0/00/00/25/83
datestamp: 2015-02-09 11:30:06
lastmod: 2015-02-09 11:30:06
status_changed: 2015-02-09 11:30:06
type: book_section
metadata_visibility: show
creators_name: Casale, Giuliano
creators_name: Tribastone, Mirco
creators_id: 
creators_id: mirco.tribastone@imtlucca.it
title: Fluid analysis of queueing in two-stage random environments
ispublished: pub
subjects: QA75
divisions: CSA
full_text_status: none
note: Eighth International Conference on the Quantitative Evaluation of Systems held in Aachen (Germany) 5 - 8 September 2011
abstract: A large number of random environments leads to Markov processes where average-environment (AVG) and near-complete-decomposability (DEC) approximations suffer unacceptably large errors. This is problematic for queueing networks in particular, where state-space explosion hinders the application of numerical methods. In this paper we introduce blending, a novel fluid-based approximation for queueing models in random environments. The technique is here first introduced for random environments with two stages. Blending estimates the equilibrium of the model by iteratively evaluating transient-analysis sub problems for each of the two stages. Each sub problem is solved by means of a very small system of ordinary differential equations, making the approach scalable and simple to implement. Random environments supported by blending are either state-independent, as for models with breakdown and repair, or state-dependent, such as for Markov-modulated queues where the service phase changes only during busy periods. Comparative results with AVG and DEC approximations prove that blending tackles the limitations of existing methods for evaluating queues in random environments.
date: 2011-09
publisher: IEEE
pagerange: 21-30
event_title: Quantitative Evaluation of Systems (QEST), 2011 Eighth International Conference on
id_number: 10.1109/QEST.2011.12
refereed: TRUE
isbn: 978-1-4577-0973-9 
book_title: Proceedings of the 8th International Conference on  Quantitative Evaluation of Systems (QEST)
official_url: http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=6042026&isnumber=6041591
citation:   Casale, Giuliano and Tribastone, Mirco  Fluid analysis of queueing in two-stage random environments.   In:  Proceedings of the 8th International Conference on Quantitative Evaluation of Systems (QEST).   IEEE, pp. 21-30.  ISBN 978-1-4577-0973-9       (2011)