Efficient Sharing of Encrypted Data

  • Krista Bennett
  • Christian Grothoff
  • Tzvetan Horozov
  • Ioana Patrascu
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 2384)


This paper describes the design of a censorship-resistant distributed file sharing protocol which has been implemented on top of gnunet, an anonymous, reputation-based network. We focus on the encoding layer of the gnunet file-sharing protocol which supports efficient dissemination of encrypted data as well as queries over encrypted data. The main idea advocated in this paper is that simple cryptographic techniques are sufficient to engineer an efficient data encoding that can make it significantly harder to selectively censor information. Our encoding allows users to share files encrypted under descriptive keys which are the basis for querying the network for content. A key property of our encoding is that intermediaries can filter invalid encrypted replies without being able to decrypt the query or the reply. Files are stored in small chunks which are distributed and replicated automatically by the Gnunet infrastructure. Additionally, data files may be stored in plaintext or encrypted form or as a combination of both and encrypted on demand.


Encode Scheme Malicious Node Encrypt Data Dictionary Attack Boolean Query 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2002

Authors and Affiliations

  • Krista Bennett
    • 1
  • Christian Grothoff
    • 1
  • Tzvetan Horozov
    • 1
  • Ioana Patrascu
    • 1
  1. 1.S3 lab and CERIAS, Department of Computer SciencesPurdue UniversityUSA

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