Understanding Handoffs in Large IEEE 802.11 Wireless Networks

摘要

As the utility of wireless technology grows, wireless networks are being deployed in more widely varying conditions. The monitoring of these networks continues to reveal key implementation deficiencies that need to be corrected in order to improve protocol operation and end-to-end performance. Using data we collected from the 67th Internet Engineering Task Force (IETF) meeting held in November 2006, we show that under conditions of high medium utilization and packet loss, handoffs can be incorrectly initiated. Using the notion of persistence and prevalence for the association of a client to an Access Point (AP), we show that although the clients were predominantly static, the handoff rate is surprisingly high. Through the analysis of the data set, we show that unnecessary handoff events not only increase the amount of management traffic in the network, but also severely impact client performance.