The Tor project is an open network for anonymous communication over the internet. Tor routes users' internet traffic through a series of volunteer-run relay nodes to conceal its origin and destination from potential surveillance or censorship.
While Tor is built for anonymity, the structure of the network and locations of many of the relay nodes is open. We built TorFlow to show the movement of data through the relay nodes of the Tor network using thousands of particles to simulate packet flow. The simulation has years of historical data so we can see how the network is used and changes over time and during significant events such as the “Arab Spring.”