Performance Analysis of the Intertwined Effects between Network Layers for 802.11g Transmissions

While the canonical behavior of today's home Internet users involves several residents concurrently executing diverse In-ternet applications, the most common home conguration is a single external connection into a wireless access point (AP) that promises to provide concurrent high-bandwidth Internet access for multiple hosts through a wireless local area network (WLAN). Recent research has attempted to assess the performance impact of hosts with weak wireless connectivity upon the other WLAN hosts by employing mea-surement studies or analytic models that focus primarily on wireless channel characteristics. This paper examines the intertwined eects on performance of the user applications, the network protocol and the wireless channel characteris-tics via carefully designed experiments that leverage pre-viously developed network measurement tools. The study provides empirical evidence that suggests the overall perfor-mance of a WLAN is not only determined by the individ-ual wireless channel qualities associated with each host, but also by the interaction of the various network layers with respect to transmission contention, queuing at the access point, transport protocol, and behavior of the specic ap-plications. These results imply that eective WLAN perfor-mance modeling needs to include details on multiple network layers