When you look at the user graphs, many of them show a weekly cycle. What's our explanation for why this occurs?
I notice it strongly when I look at the graphs for the meek pluggable transport, where usage is high on weekdays and lower on weekends. The same thing happens in some per-country graphs. (In all these graphs, the light white vertical lines are Mondays.)
https://metrics.torproject.org/userstats-bridge-transport.html?graph=usersta... https://metrics.torproject.org/userstats-relay-country.html?graph=userstats-... https://metrics.torproject.org/userstats-relay-country.html?graph=userstats-...
You can eyeball more examples in the omni-graph: https://people.torproject.org/~dcf/graphs/relays-all.pdf
But it doesn't look like that everywhere. Here are graphs for obfs3 and the United States:
https://metrics.torproject.org/userstats-bridge-transport.html?graph=usersta... https://metrics.torproject.org/userstats-relay-country.html?graph=userstats-...
And there is perhaps even the opposite pattern, where there are small peaks on the weekends, like in Germany:
https://metrics.torproject.org/userstats-relay-country.html?graph=userstats-...
Is there a usual story we tell to explain what's happening? A few hypotheses: * People use Tor at work to get their job done (work firewall blocks sites they need). * People use Tor at work to goof off. * People are relaxing and partying on the weekends, not sitting in front of a computer. * People don't have good Internet at home, so they use it more at work (and Tor use just correlates with Internet use).
George Danezis's tech report on discovering censorship events describes the weekly patterns but doesn't offer a cause. https://research.torproject.org/techreports/detector-2011-09-09.pdf "The deployed model considers a time interval of seven (7) days to model connection rates... The key reason for a weekly model is our observation that some jurisdictions exhibit weekly patterns. A 'previous day' model would then raise alarms every time weekly patterns emerge"
David Fifield
