On the Effectiveness of Continuous-Time Mixes under Flow-Correlation Based Anonymity Attacks

10.6633/IJNS.200807.7(1).16

Ye Zhu；Xin-Wen Fu；Riccardo Bettati

Anonymity ； mix ； mutual information

International Journal of Network Security

7卷1期（2008 / 07 / 01）

130 - 140

英文

In flow-based mix networks, flow correlation attacks have been proposed earlier and have been shown empirically to seriously degrade mix-based anonymous communication systems. In this paper, we theoretically analyze the effectiveness of a mix network under flow correlation attacks. Our formulae clearly show how a mix network will ultimately fail when an adversary has access to sufficiently long flow samples, independently of the type of flows (TCP or UDP).We illustrate the analysis methodology by modelling a continuous-time mix, which randomly delays each incoming packet. Our queuing-model-based analysis can provide useful guidelines for designers who develop and deploy anonymity systems.