An Accurate Technique for Measuring the Wireless Side of Wireless Networks

Jihwang Yeo$^\dag$, Moustafa Youssef$^\dag$, Tristan Henderson$^\ddag$, Ashok Agrawala$^\dag$
$^\dag$ Department of Computer Science, University of Maryland, College Park, MD 20742
{jyeo, moustafa, agrawala}@cs.umd.edu
$^\ddag$ Department of Computer Science, Dartmouth College, Hanover, NH 03755
tristan@cs.dartmouth.edu

HooHa:

Wireless monitoring (WM) is a passive approach for capturing wireless-side traffic with rich MAC/PHY layer information. WM can suffer, however, from low capture performance, i.e., high measurement loss, due to the unreliable wireless medium. In this paper, we experimentally show that WM can perform reliable and accurate measurements on wireless traffic, in actual, non-ideal channel conditions.

We demonstrate how to increase capture performance by merging traces from multiple monitoring devices. This merging enables WM to capture over 99% of the IP layer traffic and over 97% of the MAC/PHY frames in a controlled experiment. Our results indicate that WM enables reliable analysis of the collected traces, and should encourage the wireless research community to use this technique for a wide variety of research areas, such as traffic analysis, user mobility and handoff analysis, and MAC/PHY anomaly detection.