detect if a bridge is blocked in a certain country by its reported usage

We know how many IPs from each country the bridge has seeing (extra-infos bridge-ips) as well as the requests for nework statuses (dirreq-*). We can monitor those for each bridge and if they drop in a certain country we can consider this bridge being blocked there.

changed milestone to %Sponsor 96: Rapid Expansion of Access to the Uncensored Internet through Tor in China, Hong Kong, & Tibet

added Sponsor 96 Q3 labels

assigned to @meskio

added Roadmap::Future label

We'll need storage for it: #56 (closed)

Related to this topic: https://blog.torproject.org/research-problem-five-ways-test-bridge-reachability/

Maybe we can use the usage to discover bridges to test in the vantage points, and rate-limit how many we test.

In particular, the idea here is a composite passive+active idea: use the passive "has its usage dropped off?" heuristic to prioritize which bridges to send to the active scanner. The tuning will be tricky, but that is why it is an idea to investigate. :)

Right. For the original idea in this ticket, you can read more discussion about it at https://svn-archive.torproject.org/svn/projects/design-paper/blocking.html#subsec:geoip

And yes, "passive detection" is one of the five ideas in the blog post above.

Be sure to look at the "indirect scanning" idea too -- Roya at Michigan, and Paul Pearce at Georgia Tech (previously at ICSI), have deployed the "spooky scan" indirect scanning technique, and they are using it in practice for their censorship scans, and they have several times offered to work together with us to scan Tor infrastructure. I'm happy to try once more to connect people to them when the time is right.

slide deck about spooky scan, which has a bunch of terms you can google for to explore the ecosystem: https://dnsprivacy.org/attachments/48529419/52756550.pdf

For the passive approach, see also https://research.torproject.org/techreports/blocking-2011-09-15.pdf

marked this issue as related to team#79

Kind of related to that we want to document how bridge operators can test if their bridges are blocked in a certain country as IP blocks are often bidirectional: team#79

We should figure out a way for bridge operators to report when they are blocked so we don't distribute it in that country.

changed title from detect if a bridge is blocked in a certain country by it's reported usage to detect if a bridge is blocked in a certain country by its reported usage

added Backlog label and removed Roadmap::Future label

mentioned in issue bridgestrap#36 (closed)

marked this issue as related to #56 (closed)

mentioned in issue bridgedb#40054

removed Q3 label

removed Sponsor 96 label

removed milestone %Sponsor 96: Rapid Expansion of Access to the Uncensored Internet through Tor in China, Hong Kong, & Tibet

added Roadmap::Future label and removed Backlog label

unassigned @meskio

marked this issue as related to censorship-analysis#40035

mentioned in issue censorship-analysis#40035

mentioned in issue lox#57