## Scheduling for Multiple Flows Sharing a Time-Varying Channel: The Exponential Rule (2000)

Venue: | American Mathematical Society Translations, Series |

Citations: | 133 - 13 self |

### BibTeX

@ARTICLE{Shakkottai00schedulingfor,

author = {Sanjay Shakkottai and Alexander L. Stolyar},

title = {Scheduling for Multiple Flows Sharing a Time-Varying Channel: The Exponential Rule},

journal = {American Mathematical Society Translations, Series},

year = {2000},

volume = {2},

pages = {2002}

}

### Years of Citing Articles

### OpenURL

### Abstract

We consider the following queueing system which arises as a model of a wireless link shared by multiple users. Multiple flows must be served by a "channel" (server). The channel capacity (service rate) changes in time randomly and asynchronously with respect to different flows. In each time slot, a scheduling discipline (rule) picks a flow for service based on the current state of the channel and the queues. We study a scheduling rule, which we call the exponential rule, and prove that this rule is throughput-optimal, i.e., it makes the queues stable if there exists any rule which can do so. In the proof we use the fluid limit technique, along with a separation of time scales argument. Namely, the proof of the desired property of a "conventional" fluid limit involves a study of a different fluid limit arising on a "finer" time scale. In our companion paper [12] it is demonstrated that the exponential rule can be used to provide Quality of Service guarantees over a shared wireless link.

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Citation Context ... of time scales argument. Namely, the proof of the desired property of a "conventional" fluid limit involves a study of a different fluid limit arising on a "finer" time scale. In =-=our companion paper [12]-=- it is demonstrated that the exponential rule can be used to provide Quality of Service guarantees over a shared wireless link. Part of this work was carried out when this author was an intern at Bell... |

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Citation Context ...s queues stable in any system for which stability is feasible at all, with any other rule. The specific variable channel scheduling model we study is the same as that in [2] (and its extended version =-=[1]-=-), where a scheduling rule called Modified Largest Weighted Delay First (M-LWDF) was proposed and proved to be throughput optimal. The Exponential rule was introduced in [1], but not studied analytica... |

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