FLIP: A Framework for Leveraging eBPF to Augment WiFi Access Points and Investigate Network Performance

Monitoring WiFi networks is essential to gain insight into the network operation and develop methods capable of reacting to network dynamics. However, research and development in this field are hindered because there is a lack of a framework that can be easily extended to collect various types of monitoring data from the WiFi stack. In this paper, we propose FLIP, a framework for leveraging eBPF to augment WiFi access points and investigate the performance of WiFi networks. Using this framework, we focus on two important aspects of monitoring the WiFi stack. First, considering the high delay experienced by packets at access points, we show how switching packets from the wired interface to the wireless interface can be monitored and timestamped accurately at each step. We build a testbed using FLIP access points and investigate the factors affecting packet delay experienced in access points. Second, we present a novel approach that allows access points to track the duty-cycling pattern and energy consumption of their associated stations accurately and without the need for any external energy measurement tools. We validate the high energy measurement accuracy of FLIP by empirical experiments and comparisons against a commercial tool.