Monitoring wireless networks: performance assessment of sniffer architectures

This paper assesses the performance of wireless sniffers built using off-the-shelf hardware and software. Such an analysis tool is commonly found in wireless testbeds given its low cost. The goal of this study is to provide a framework to assess the performance of measurements obtained using this popular tool. Among various contributions, the study shows the importance of precisely checking the behavior of the hardware used for communications and for monitoring in order to validate the traces obtained. It also presents a methodology to assess the performance of wireless sniffers based on obtaining a correlation factor between traces captured by independent devices. The paper reveals, in addition, a new type of loss in sniffer captures, the saturation loss, that completes previous work on this topic. Finally, the paper also studies the behavior of architectures using several sniffers in a single computer. It reveals how, again in this case, the hardware chosen is critical to obtain desired performance.