  We propose a traffic confirmation attack on low-latency mix networks based on
computing robust real-time binary hashes of network traffic flows. Firstly, we
adapt the Coskun-Memon Algorithm to construct hashes that can withstand network
impairments to allow fast matching of network flows. The resulting attack has a
low startup cost and achieves a true positive match rate of 80% when matching
one flow out of 9000 with less than 2% false positives, showing traffic
confirmation attacks can be highly accurate even when only part of the network
traffic flow is seen. Secondly, we attack probabilistic padding schemes
achieving a match rate of over 90% from 9000 network traffic flows, showing
advanced padding techniques are still vulnerable to traffic confirmation
attacks.
