Effort-limited Fair (ELF) Scheduling for Wireless Networks

13 years 9 months ago

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— While packet scheduling for wired links is a maturing area, scheduling of wireless links is less mature. A fundamental difference between wired and wireless links is that wireless media can exhibit substantial rates of link errors, resulting in signiﬁcant and unpredictable loss of link capacity. This capacity loss results in a special challenge for wireless schedulers. For example, a Weighted Fair Queue (WFQ) scheduler assumes an error-free link and speciﬁes how ﬂows should share the link capacity. However, this speciﬁcation is not sufﬁcient to determine the correct outcome when link capacity is sharply reduced, because ﬂows that have been allocated the same weights may differ greatly in their ability to tolerate throughput loss. In this paper, we ﬁrst describe the wireless scheduling challenge in terms of an effort-outcome disconnection. Next we propose a novel notion of fairness for wireless links, effort-limited fairness (ELF), which extends WFQ via dynamic weight ...

David A. Eckhardt, Peter Steenkiste

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