Mining Urban WiFi QoS Factors: A Data Driven Approach

WiFi networks play a significant role in providing today's wireless connectivity, therefore, understanding and improving WiFi network performance is important for today's mobile applications and services. Previous studies conducted to investigate WiFi network performance have generally been performed using specific types of WiFi networks in relatively small areas and have been limited by either the scale of the studied WiFi access points (APs) or by the number of users. This paper describes a country-wide measurement study on WiFi network performance with the goal of determining which factors affect the quality of service (QoS) of high-density WiFi networks. We use a crowdsourced approach to study both the latency and bandwidth experienced by users in different types of WiFi networks. Our findings indicate that (1) WiFi network performance is correlated not only with signal strength but also with factors such as time, (2) the latency and bandwidth experienced by users generally exhibit different patterns and are affected differently by the studied factors, and (3) users experience significantly different QoS from different nearby APs, which suggests that providing users with better information when choosing a WiFi connection can yield more satisfactory results. We also provide insights on how such findings can be utilized to improve AP deployments and optimize association strategies.