Evading Censorship with Browser-Based Proxies

  • David Fifield
  • Nate Hardison
  • Jonathan Ellithorpe
  • Emily Stark
  • Dan Boneh
  • Roger Dingledine
  • Phil Porras
Part of the Lecture Notes in Computer Science book series (LNCS, volume 7384)


While Internet access to certain sites is blocked in some parts of the world, these restrictions are often circumvented using proxies outside the censored region. Often these proxies are blocked as soon as they are discovered. In this paper we propose a browser-based proxy creation system that generates a large number of short-lived proxies. Clients using the system seamlessly hop from one proxy to the next as these browser-based proxies appear and disappear. We discuss a number of technical challenges that had to be overcome for this system to work and report on its performance and security. We show that browser-based short-lived proxies provide adequate bandwidth for video delivery and argue that blocking them can be challenging.


Defense Advance Research Project Agency Network Address Translation Visit Duration USENIX Security Symposium Rendezvous Protocol 
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Copyright information

© Springer-Verlag Berlin Heidelberg 2012

Authors and Affiliations

  • David Fifield
    • 1
  • Nate Hardison
    • 1
  • Jonathan Ellithorpe
    • 1
  • Emily Stark
    • 2
  • Dan Boneh
    • 1
  • Roger Dingledine
    • 3
  • Phil Porras
    • 4
  1. 1.Stanford UniversityUSA
  2. 2.Massachusetts Institute of TechnologyUSA
  3. 3.The Tor ProjectUSA
  4. 4.SRI InternationalUSA

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