Countermeasure against fingerprinting attack in Tor by separated contents retrieval

Abstract

Tor (The Onion Router) realizes that anonymous web surfing without revealing the user’s identity. However, A. Panachenko et al. reveals that an onion router that directly communicates with a user can infer which website a user accesses by leveraging site-specific traffic features, e.g., volume and time, and this attack is called the fingerprinting attack. In this paper, we propose a countermeasure against the fingerprinting attack by obfuscating site-specific traffic features. The idea is to establish two distinct Tor connections and to separately request text-based contents and image-based one through them. We show the effectiveness of our scheme with experiments.