From a Trickle to a Flood: Active Attacks on Several Mix Types

  • Andrei Serjantov
  • Roger Dingledine
  • Paul Syverson
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 2578)


The literature contains a variety of different mixes, some of which have been used in deployed anonymity systems. We explore their anonymity and message delay properties, and show how to mount active attacks against them by altering the traffic between the mixes. We show that if certain mixes are used, such attacks cannot destroy the anonymity of a particular message completely. We work out the cost of these attacks in terms of the number of messages the attacker must insert into the network and the time he must spend. We discuss advantages and disadvantages of these mixes and the settings in which their use is appropriate. Finally, we look at dummy traffic and SG mixes as other promising ways of protecting against the attacks, point out potential weaknesses in existing designs, and suggest improvements.


Active Attack Commitment Scheme Message Delay Attack Message Target Message 
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 2003

Authors and Affiliations

  • Andrei Serjantov
    • 1
  • Roger Dingledine
    • 2
  • Paul Syverson
    • 3
  1. 1.University of Cambridge Computer LaboratoryUK
  2. 2.The Free Haven ProjectUSA
  3. 3.Naval Research LaboratoryUSA

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