Understanding the Impact of AP Density on WiFi Performance Through Real-World Deployment

802.11 (WiFi) networks have become increasingly important for our daily lives. However, previous work has shown that enterprise WiFi performance is often unsatisfactory and that over-utilization and interference from rogue APs are the two primary reasons. To address the above problem, this paper proposes to improve the capacity of WiFi infrastructures by increasing the enterprise AP deployment density, as well as disabling the wired Internet access in buildings to eliminate rogue APs and their interference. We deployed several WiFi networks with different AP density and vendors on Tsinghua campus. Based on the measurement results from our real-world deployments, we made three main observations: 1) in general, higher AP density improves WiFi performance; 2) over-dense deployment with unnecessarily high transmission power can worsen WiFi performance. 3) choice of AP vendors also has an impact on WiFi performance.