Censors’ Delay in Blocking Circumvention Proxies

This is the supporting web page for a research project to examine how quickly censorship circumvention proxies (Tor bridges) are noticed and blocked by censors after being made public. We conducted the research by active measurement of proxies from the United States, China, Iran, and Kazakhstan.

David Fifield, Lynn Tsai, Qi Zhong
University of California, Berkeley
(Authors are listed alphabetically.)


Code & Data

Probe source code and data
git clone https://www.bamsoftware.com/git/repo.eecs.berkeley.edu/proxy-probe.git
Paper source code (includes graphing code)
git clone https://www.bamsoftware.com/git/repo.eecs.berkeley.edu/proxy-probe-paper.git
Dates of notable bridge-related events
significant_dates.txt (14 KB)
Kazakhstan code and data (more intensive, full obfs4 bootstrap tests)

The probe sites in probe.csv are identified by code name.

Backup of data at archive.org: proxy-probe-data.