Fair Access Provisioning through Contention Parameter Adaptation in the IEEE 802.11e Infrastructure Basic Service Set

TL;DR

This paper proposes a dynamic, standard-compliant framework for fair access in IEEE 802.11e networks, adapting EDCA parameters at the Access Point to address uplink-downlink unfairness while considering TCP, UDP, and QoS needs.

Contribution

It introduces a novel measurement-based EDCA parameter adaptation method that accounts for different flow types and QoS requirements, enhancing fairness and efficiency.

Findings

Achieves fair uplink and downlink access for TCP and UDP flows.

Maintains QoS for real-time flows.

Improves fairness in heterogeneous wireless networks.

Abstract

We present the station-based unfair access problem among the uplink and the downlink stations in the IEEE 802.11e infrastructure Basic Service Set (BSS) when the default settings of the Enhanced Distributed Channel Access (EDCA) parameters are used. We discuss how the transport layer protocol characteristics alleviate the unfairness problem. We design a simple, practical, and standard-compliant framework to be employed at the Access Point (AP) for fair and efficient access provisioning. A dynamic measurement-based EDCA parameter adaptation block lies in the core of this framework. The proposed framework is unique in the sense that it considers the characteristic differences of Transmission Control Protocol (TCP) and User Datagram Protocol (UDP) flows and the coexistence of stations with varying bandwidth or Quality-of-Service (QoS) requirements. Via simulations, we show that our solution provides short- and long-term fair access for all stations in the uplink and downlink employing TCP and UDP flows with non-uniform packet rates in a wired-wireless heterogeneous network. In the meantime, the QoS requirements of coexisting real-time flows are also maintained.