Yesterday, Kenneth Freeman posted a note to the tor-relays list drawing attention to a new resource called TorFlow. TorFlow is a beautiful visualisation of Tor network traffic around the world. It enables you to see where traffic is concentrated (Europe) and where there is almost none (Australasia). Having the data overlaid on a world map gives a startling picture of the unfortunate concentration of Tor nodes in particular locations.
I recently moved my own relay from Amsterdam (190 relays) to London (133) but the network needs much more geo-diversity. Unfortunately, international bandwidth costs are lowest is the areas where relays are currently located. Given that the relays are all (well, nearly all…..) run by volunteers like me and funded out of their own pockets it is perhaps not surprising that this concentration should occur. But it is not healthy for the network.
There appears to be a particularly intriguing concentration of 16 relays on a tiny island in the Gulf of Guinea. Apparently this is an artifact though because those relays are all at (0, 0) which I am told GeoIP uses as a placeholder for “unknown” (in fact, GeoIP location is a somewhat imprecise art so there may be other anomalies in the data.)