In this study, we propose a comprehensive approach combining active and passive measurements to efficiently evaluate the performance and troubleshoot wireless LANs. Our existing active measurement tool, SINDAN, conducts multi-layer verification from the wireless layer to the application layer. However, it may overlook the impact of minor anomalies in lower layers on the measurement results of other layers. To address this issue, we perform wireless frame and IP packet captures in parallel with the active measurements of wireless LANs, synchronizing the timestamps of each measurement item. This enables us to conduct corre- lation analysis between the measurement contents and the captured frames. Our proposed method makes it possible to determine whether problems detected in upper-layer measurements originate from issues in lower layers during multi-layer measurements. We apply the proposed method to the following three scenarios to verify its effectiveness:
1) Communication failures caused by radio interference, 2) Performance degradation due to wireless LAN access point configuration, 3) Throughput reduction caused by traffic congestion on wireless LANs.