An Effective Website Fingerprinting Defense Based on Traffic Splitting and Padding

Due to Tor as an anonymity communication network system can protect user privacy, so all the attack arithmetic of Website Fingerprinting (WF) attacks were arranged to destroy the user anonymity by analyzing users' traffic. To solve the problems existed in a lot of various WF defense systems developed to resist WF attacks, a novel WF defense, consisting of a traffic splitting module and a padding module, was proposed based on traffic splitting with padding (SWP), reducing the spending of these WF defense methods and advancing defense effectiveness. The traffic splitting module was arranged to split traffic in a random number of multiple circuits and send to different circuits with a circuit-switching strategy based on packet intervals. Meanwhile, the padding module was designed to utilize two sub-modules, Break Burst, and Extend Burst, to inject padding packets into the incoming and outgoing bursts respectively, to further obfuscate the traffic patterns on each circuit. In the closed-world setting, the analysis results show that the proposed algorithm can further reduce RF's precision by 18.54% and RF's recall by 20.25% compared to its comparable HyWF. Comparing with CoMPS, the proposed algorithm can further reduce RF's precision by 2.72% and RF's recall by 5.23% with fewer circuits. Experimental results show that the proposed algorithm can outperform to comparable algorithms and lower defense spending. © 2024 Beijing Institute of Technology. All rights reserved.