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arXiv · 1206.5673

A retrial system with two input streams and two orbit queues

Konstantin Avrachenkov·Philippe Nain·Uri Yechiali
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Abstract

Two independent Poisson streams of jobs flow into a single-server service system having a limited common buffer that can hold at most one job. If a type-i job (i=1,2) finds the server busy, it is blocked and routed to a separate type-i retrial (orbit) queue that attempts to re-dispatch its jobs at its specific Poisson rate. This creates a system with three dependent queues. Such a queueing system serves as a model for two competing job streams in a carrier sensing multiple access system. We study the queueing system using multi-dimensional probability generating functions, and derive its necessary and sufficient stability conditions while solving a boundary value problem. Various performance measures are calculated and numerical results are presented.

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Konstantin Avrachenkov, Philippe Nain, Uri Yechiali. 2012-06-22. A retrial system with two input streams and two orbit queues. https://arxiv.org/abs/1206.5673

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