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TorBricks: Blocking-Resistant Tor Bridge Distribution

  • Mahdi Zamani
  • Jared Saia
  • Jedidiah Crandall
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 10616)

Abstract

Tor is currently the most popular network for anonymous Internet communication. It critically relies on volunteer nodes called bridges to relay Internet traffic when a user’s ISP blocks connections to Tor. Unfortunately, current methods for distributing bridges are vulnerable to malicious users who obtain and block bridge addresses. In this paper, we propose TorBricks, a protocol for privacy-preserving distribution of Tor bridges to n users, even when an unknown number \({t < n}\) of these users are controlled by a malicious adversary. TorBricks distributes \(O(t\log {n})\) bridges and guarantees that all honest users can connect to Tor with high probability after \(O(\log {t})\) rounds of communication with the distributor. Our empirical evaluations show that TorBricks requires at least 20x fewer bridges and two orders of magnitude less running time than the state-of-the-art.

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Copyright information

© Springer International Publishing AG 2017

Authors and Affiliations

  1. 1.Visa ResearchPalo AltoUSA
  2. 2.University of New MexicoAlbuquerqueUSA

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