Blending Different Latency Traffic with Alpha-mixing

  • Roger Dingledine
  • Andrei Serjantov
  • Paul Syverson
Part of the Lecture Notes in Computer Science book series (LNCS, volume 4258)


Currently fielded anonymous communication systems either introduce too much delay and thus have few users and little security, or have many users but too little delay to provide protection against large attackers. By combining the user bases into the same network, and ensuring that all traffic is mixed together, we hope to lower delay and improve anonymity for both sets of users.

Alpha-mixing is an approach that can be added to traditional batching strategies to let senders specify for each message whether they prefer security or speed. Here we describe how to add alpha-mixing to various mix designs, and show that mix networks with this feature can provide increased anonymity for all senders in the network. Along the way we encounter subtle issues to do with the attacker’s knowledge of the security parameters of the users.


Security Parameter Target Message Passive Adversary Edge Case Active Attacker 
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 2006

Authors and Affiliations

  • Roger Dingledine
    • 1
  • Andrei Serjantov
    • 1
  • Paul Syverson
    • 2
  1. 1.The Free Haven Project 
  2. 2.Naval Research Laboratory 

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