Fairness in Collision-Free WLANs

TL;DR

This paper enhances the CSMA/ECA protocol with hysteresis and fair-share properties, enabling fair, collision-free WLANs with high throughput even with many contenders, outperforming CSMA/CA.

Contribution

Introduces hysteresis and fair-share features to CSMA/ECA, improving fairness and throughput in collision-free WLAN scheduling.

Findings

High throughput maintained with many contenders

Enhanced fairness across nodes with different contention windows

Performance surpasses traditional CSMA/CA

Abstract

CSMA/ECA is a contention protocol that makes it possible to construct a collision-free schedule by using a deterministic backoff after successful transmissions. In this paper, we further enhance the CSMA/ECA protocol with two properties that allows to fairly accommodate a large number of contenders in a collision-free schedule. The first property, called hysteresis, instructs the contenders not to reset their contention window after successful transmissions. Thanks to hysteresis, the protocol sustains a high throughput regardless of the number of contenders. The second property, called fair-share, preserves fairness when different nodes use different contention windows. We present simulations results that evidence how these properties account for performance gains that go even further beyond CSMA/CA.