On the performance characteristics of WLANs: revisited

Wide-spread deployment of infrastructure WLANs has made Wi-Fi an integral part of today’s Internet access technology. Despite its crucial role in affecting end-to-end performance, past research has focused on MAC protocol enhancement, analysis and simulation-based performance evaluation without sufficient consideration for modeling inaccuracies stemming from inter-layer dependencies, including physical layer diversity, that significantly impact performance. We take a fresh look at IEEE 802.11 WLANs, and using a combination of experiment, simulation, and analysis demonstrate its surprisingly agile performance traits. Our main findings are two-fold. First, contention-based MAC throughput degrades gracefully under congested conditions, enabled by physical layer channel diversity that reduces the effective level of MAC contention. In contrast, fairness and jitter significantly degrade at a critical offered load. This duality obviates the need for link layer flow control for throu...

• Type: Conference
• Year: 2005
• Where: SIGMETRICS
• Authors: Sunwoong Choi, Kihong Park, Chong-kwon Kim
• Keywords: MAC Throughput Degrades, Physical Layer, SIGMETRICS 2005, Throughput