An Analysis of the Degradation of Anonymous Protocols.
Matthew Wright, Micah Adler, Brian Neil Levine, Clay Shields · 2002
There have been a number of protocols proposed for anonymous network communication. In this paper we prove that when a particular initiator continues communication with a particular responder across path reformations, existing protocols are subject to attacks by corrupt group members that degrade the anonymity of each protocol over time. We use this result to place an upper bound on how long existing protocols including Crowds, Onion Routing, Hordes, and DC-Net, can maintain anonymity in the face of the attacks described. Our results show that fully-connected DC-Net is the most resilient to these attacks, but is subject to simple denial-of-service attacks. Additionally, we show how a variant of the attack allows attackers to setup other participants to falsely appear to be the initiator of a connection.