Using Trust to Resist Censorship in the Presence of Collusion

  • Andriy Panchenko
  • Lexi Pimenidis
Part of the IFIP International Federation for Information Processing book series (IFIPAICT, volume 232)


Censorship resistance deals with an attempt to prevent censors from the acquaintance of distribution of a particular content through the network. Providing resistance against censoring is a very challenging and difficult task to achieve. However it is vital for the purpose of freedom of speech, mind and achievement of democratic principles in todays society.

In this paper we define a model of a censorship resistant system. Thereafter we propose to split the problem of resisting censorship into the following two sub-problems: a trusted directory and steganographic data transfer. The directory is used in order to prolong contacts among peers based on their reputation in a way, that honest members get contacts only to other honest peers and colluded members remain isolated. Furthermore, we aim to provide an analysis of a trusted directory for reputation and its implications on censorship resistant systems. To this end we define a set of properties that such a directory has to fulfill and develop a proposal for the implementation. Finally we provide a simulation-based validation of our approach.


Communication Partner Cluster User Private Information Retrieval Trust Vector Honest User 


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Copyright information

© International Federation for Information Processing 2007

Authors and Affiliations

  • Andriy Panchenko
    • 1
  • Lexi Pimenidis
    • 1
  1. 1.Computer Science Department — Informatik IVRWTH Aachen UniversityAachenGermany

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