While the canonical behavior of today's home Internet users involves several residents concurrently executing diverse Internet applications, the most common home configuration 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 measurement studies or analytic models that focus primarily on wireless channel characteristics. This paper examines the intertwined effects on performance of the user applications, the network protocol and the wireless channel characteristics via carefully designed experiments that leverage previously developed network measurement tools. The study provides empirical evidence that suggests the overall performance of a WLAN is not only determined by the individual 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 specific applications. These results imply that effective WLAN performance modeling needs to include details on multiple network layers.
['Jon Gretarsson', 'Feng Li', 'Mingzhe Li', 'Ashish Samant', 'Huahui Wu', 'Mark Claypool', 'Robert E. Kinicki']
Performance analysis of the intertwined effects between network layers for 802.11g transmissions