WiSlow: A Wi-Fi network performance troubleshooting tool for end users

Slow Internet connectivity is often caused by poor Wi-Fi performance. The main reasons of such performance degradation include channel contention and non-Wi-Fi interference. Although these problem sources can be easily removed in many cases once they are discovered, it is difficult for end users to identify the sources of such interference. We investigated the characteristics of different sources that can degrade Wi-Fi performance, and developed WiSlow, a software tool that diagnoses the root causes of poor Wi-Fi performance using user-level network probes, and leveraging peer collaboration to identify the physical location of these causes. WiSlow uses two main methods: packet loss analysis and 802.11 ACK number analysis. The accuracy of WiSlow exceeds 90% when the sources are close to Wi-Fi devices. Also, our experiment proves that the collaborative approach is feasible for determining the relative location of an interfering device.