Performance tuning of Infrastructure-Mode wireless LANs

—Conventional wisdom about 802.11 WLANs dictates that as the number of active users increases, the contention windows (CW) of all the contending users needs to increase to prevent collision losses. However, given the increasing data rates of 802.11 standards, the fraction of time spent not transmitting information (as a result of back-off) is also increasing, leading to reduced throughput when compared to the theoretical maximum. While there appears to be an inherent conflict between reducing collisions by increasing the CW and reducing overhead by decreasing the CW, we demonstrate in this paper that this conflict can be eliminated in Infrastructure-Mode wireless LANs (I-WLAN) where downlink TCP and UDP flows dominate. Unlike the traditional trend of WLAN performance analysis that assumes that all the stations are greedy, we consider the case in which only the access point (AP) is greedy while the mobile users in the cell react to the information sent to them. This setting capture...

• Type: Journal
• Year: 2010
• Where: WIOPT
• Authors: Yigal Bejerano, Hyoung-Gyu Choi, Seung-Jae Han, Thyaga Nandagopal
• Keywords: 802.11, Computer Networks, Currentgeneration 802.11 Chip-sets, Infrastructure-mode Wireless Lans, WIOPT 2010