Subrosa: An Experimental Platform For Studying Timing Analysis Of Real Time Anonymity Systems

Timing analysis poses a significant challenge for the mix based anonymous systems that wish to support low-latency applications like web browsing, instant messaging and Voice over IP (VOIP). Research in this area so far has been done through simulations on ad hoc simulators or non practical local area networks. We developed SubRosa, an experimental platform for studying timing analysis of real time anonymity systems to facilitate the study of Tor like low-latency anonymous systems. We present results of experiments on a real distributed network test bed PlanetLab, where we studied timing analysis attacks and some of the defenses to protect against such attacks. We validate the simulated results obtained for defensive dropping by Levine et al in 2004 on PlanetLab using SubRosa. We also propose a new light weight defense based on the basic mix principal called γ-buffering and evaluate the initial results from the experiments with γ-buffering on PlanetLab.