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arXiv · 2303.17544

TorKameleon: Improving Tor's Censorship Resistance with K-anonymization and Media-based Covert Channels

Afonso Vilalonga·João S. Resende·Henrique Domingos
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Abstract

Anonymity networks like Tor significantly enhance online privacy but are vulnerable to correlation attacks by state-level adversaries. While covert channels encapsulated in media protocols, particularly WebRTC-based encapsulation, have demonstrated effectiveness against passive traffic correlation attacks, their resilience against active correlation attacks remains unexplored, and their compatibility with Tor has been limited. This paper introduces TorKameleon, a censorship evasion solution designed to protect Tor users from both passive and active correlation attacks. TorKameleon employs K-anonymization techniques to fragment and reroute traffic through multiple TorKameleon proxies, while also utilizing covert WebRTC-based channels or TLS tunnels to encapsulate user traffic.

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Afonso Vilalonga, João S. Resende, Henrique Domingos. 2023-03-30. TorKameleon: Improving Tor's Censorship Resistance with K-anonymization and Media-based Covert Channels. https://arxiv.org/abs/2303.17544

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