Censored Planet

What is Censored Planet?

Censored Planet is a system for continuously monitoring global Internet censorship. It uses novel measurement techniques that remotely detect instances of interference almost anywhere on the Internet without end-user participation. Previous approaches relied on the deployment of special hardware or software by volunteers in censored regions -- eliminating this requirement allows for significantly better coverage, lower costs, and reduced ethical risk. This system allows us to continuously monitor the deployment of network interference technologies, track policy changes in censoring nations, and better understand the targets of interference. We seek to make opaque censorship practices more transparent at a global scale to help counter the proliferation of restrictions to online freedom.


We collect data from our three flagship tools Augur, Satellite, and Quack to provide information on internet censorship around the world and measure remote interference.



Internet-Wide Measurement of Network Layer Censorship

Augur is a system that utilizes TCP/IP side channels to measure reachability between two Internet locations without directly controlling a measurement vantage point at either location. It is a scalable, statistically robust methods to infer network-layer filtering, and capable of performing continuous monitoring of global censorship. It is currently deployed and runs Internet-wide disruption tests in nearly 180 countries against sites known to be frequently blocked.


Global Measurement and Detection of DNS-Layer Censorship

Satellite measures global trends in website deployment and accessibility via the consistency of DNS records. Satellite watches DNS resolution through active measurements of DNS resolvers across the IPv4 address space. A data-set of the alexa top 10,000 domains is collected each week. Satellite is committed to openness, with all code and data made publicly available.


Scalable Remote Measurement of Application-Layer Censorship

Quack is a technique for detecting content-level censorship. Quack sacrifices idenitification of tightly controlled DPI behavior in exchange for broad measurements of keywords and protocol disruption.