Using signal processing to analyze wireless data traffic
Craig Partridge, David Bruce Cousins, Alden W. Jackson, Rajesh Krishnan, Tushar Saxena, W. Timothy Strayer · 2002
Experts have long recognized that theoretically it was possible to perform traffic analysis on encrypted packet streams by analyzing the timing of packet arrivals (or transmissions). We report on experiments to realize this possiblity using basic signal processing techniques taken from acoustics to perform traffic analysis on encrypted transmissions over wireless networks. While the work discussed here is preliminary, we are able to demonstrate two very interesting results. First, we can extract timing information, such as round-trip times of TCP connections, from traces of aggregated data traffic. Second, we can determine how data is routed through a network using coherence analysis. These results show that signal processing techniques may prove to be valuable network analysis tools in the future.