Johannes Kepler University Linz, Austria
Tor, Anonymization, Traffic Analysis.
Information and Systems Security
Privacy Enhancing Technologies
The Tor anonymization network supports (and is widely used for) circumventing censorship, evading
intrusive mass-surveillance, and generally protecting privacy of Internet users. However, it also carries
traffic that is illegal in various jurisdictions. It is still an open question how to deal with such illegal traffic
in the Tor network, balancing the fundamental human right for privacy with the need for assisting executive
forces. By operating and monitoring a high-bandwidth Tor exit node as both a technical and legal
experiment, we statistically analyse where popular servers are located and how they are used based on
connection metadata of actual exit node usage. Through this we identify inter alia that cooperation only in
comparatively few countries would be needed – or any illegal use would be very small. In this paper, we
provide more in-depth statistical insight into Tor exit node traffic than previously publicly available.