Breaking an efficient anonymous channel

  • Birgit Pfitzmann
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 950)


At Eurocrypt 1993, Park, Itoh, and Kurosawa presented an “all/nothing election scheme and anonymous channel”. The schemes are based on the mix-net and the election scheme constructed from this anonymous channel (Chaum 1981). One of the two main improvements is that the messages sent by normal participants are significantly shorter in the two new anonymous channels. However, we show several successful attacks on these channels and thus on the secrecy of the votes in the election scheme. They break the first, more efficient channel completely. For the second channel and the election protocol, we present some countermeasures against all our attacks. Note, however, that we do not guarantee security even then, and that the specification of that channel is somewhat weaker than that of the original mix-net.


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Copyright information

© Springer-Verlag Berlin Heidelberg 1995

Authors and Affiliations

  • Birgit Pfitzmann
    • 1
  1. 1.Institut für InformatikUniversität HildesheimHildesheimGermany

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