The number of governments that routinely block web sites is increasing, according to the most comprehensive survey of internet filtering yet. Meanwhile, the same study suggests that techniques for blocking undesirable content are growing ever more sophisticated.
Previous reports of government internet filtering have been limited to specific countries, such as China, Iran and Cuba, says Rafal Rohozinski, of the Open Net Initiative (ONI), which produced the report. The ONI is a partnership between the University of Cambridge, the University of Oxford, Harvard University and Toronto University.
Rohozinski says such reports have been based largely on anecdotal information and spot sampling. “This is the first attempt to create a rather comprehensive survey across a large number of countries, looking comparatively at whether they filter, what they filter and for what reasons,” he says.
In its report, the ONI states that governments in at least 25 countries regularly block access to internet sites for political, social or security reasons. It says that Burma, China, Iran, Syria, Tunisia and Vietnam filter political content, such as sites belonging to political opposition parties. Elsewhere, Saudi Arabia, Iran, Tunisia and Yemen filter for social reasons: for example by blocking access to pornography, gay and lesbian content and gambling sites.
Wider restrictions
By comparing their findings to earlier reports, the authors conclude that filtering is currently increasing worldwide. They also believe that governments are extending restrictions beyond just information websites to other online services, such as internet telephony network Skype.
Furthermore, the team discovered so-called “event-based” filtering an upsurge in restrictions during significant political periods such as elections.
In 2006, the ONI created software that automatically visits a list of web sites and reports back to a central computer on whether the site is available. The software runs simultaneously on a computer inside a country being tested, and in another country.
This makes it possible to distinguish between active filtering and a temporary outage.
But Rohozinski adds that, in many countries, filtering probably goes well beyond what the tests reveals.
Oppressive controls
Based on other evidence, he says 16 further countries may control internet access in ways not detected by the ONI tests, for example, by arresting people who visit certain sites at internet cafes, something that has happened in Uzbekistan. “We may be understating the problem in a rather big way,” says Rohozinski
“As internet censorship and surveillance grow, there’s reason to worry about the implications of these trends for human rights, political activism and economic development around the world,” says Jonathan Zittrain, a principle investigator at the ONI.
