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Google China headquarters

The headquarters of Google China before the search engine company exited the country earlier this year and started routing searches from China through its Hong Kong site.

Credit: Josh Chin

Governments attempting to strangle access to sensitive information are nothing new. Throughout history, authorities have seized printing presses, jammed radio broadcasts, and blocked television programming in order to control hearts and minds. "In many countries, censorship is a deeply entrenched practice," notes Andrew Lih, visiting professor of new media at the University of Southern California's Annenberg School for Communication and Journalism.

However, in the age of the Internet, the stakes are higher and the challenges associated with controlling information are greater. According to Reporters Without Borders, a dozen countries—including China, Iran, and Saudi Arabia—are on its annual "Enemies of the Internet" list, which is based on the number of citizens arrested, harassed, or threatened in the previous year for their online activities and on how the nations monitor the Internet and limit access. Eleven other countries made Reporters Without Borders' "Under Surveillance" list, and even nations that trumpet freedom sometimes rely on censorship techniques. In addition, Reporters Without Borders states that 118 bloggers and other netizens are currently residing in jails because of content they have posted.

In fact, a growing number of governments use methods—including Domain Name System blocking, Internet Protocol blocking, or Uniform Resource Locator keyword filters (see "How Censorship Works" on right)—to make popular Web sites, such as Facebook, YouTube, and Twitter, inaccessible to their citizens. Some also force Google and other search engines to self-censor their results. In most instances, the goal is to control the political dialogue, but authorities also use these techniques to create favorable conditions for government-controlled businesses and others operating in their country.

Not surprisingly, citizens of these countries are increasingly turning to software tools that circumvent blocks and filters through the use of proxy servers or virtual private networks (VPNs). "Governments impose blocks and restrictions and people try and often succeed in finding ways around them," observes Vadim Isakov, scholar in residence at Ithaca University's School of Communications.

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A New Era of Openness?

When the Internet achieved a tipping point of popularity in the mid-1990s pundits argued that it would usher in a new era of openness. For the most part, this prediction has proved true. However, the challenges associated with filtering and blocking content haven't stopped many governments from imposing restrictions. China, Turkmenistan, Uzbekistan, Saudi Arabia, and Iran are among the most aggressive censors, says Isakov.

Yet even countries such France, Germany, Poland, Thailand, and Turkey have turned to censorship—sometimes forcing Google to restrict access to sites, files, and reports. The aforementioned European countries, for example, ban materials that support Nazi causes, and Thailand won't allow unflattering material—including videos—of its monarch. At the same time, India has ordered Google to remove content that the government flags as "indecent, immoral, or threatening the public order."

Google recently brought the issue of Internet censorship to the forefront due to its troubled relationship with the Chinese government. In 2006, the search engine provider introduced a China-based search page with censored results. Many observers criticized Google for bowing to pressure from the Chinese government. By early 2009, China began blocking Google's YouTube site and other online services. Finally, in January 2010, Google indicated it wasn't willing to censor search results and was considering pulling out of China.

After a series of hacker attacks originating from China in February and unsuccessful negotiations with the Chinese government, Google closed its China search site and began rerouting searches from China through its Hong Kong site. However, any searches conducted from China come back censored. While many applauded the decision to halt censored service in China, Google also was criticized by Chinese officials and citizens.

In fact, no nation has received as much public scrutiny as China and its so-called "Great Firewall." Only a few fiber-optic cables—think of them as checkpoints—manage data flowing into the country. Nevertheless, 99% of content flows through untouched, Lih says. In most instances, there's no easy or definable way to determine exactly what's being blocked and what citizens can access.

That's because China, like many countries, blocks sites sporadically and in no systematic way. "For one thing, there's no official policy or admission that the practice is taking place in China. For another, there's no documentation," Lih says. The net effect for those browsing the Web or attempting to connect to a blocked service is a "Connection Reset" message that the requested Web page or service is unavailable. "It looks as though you've encountered technical difficulties or a temporary disruption," Lih says.

Worse, the interruptions are erratic and unpredictable. A news site such as CNN or BBC, for example, might be available at one moment but disappear seconds later if a story about a sensitive subject, such as Tibet or Tiananmen Square, is published.

Observers say these interruptions, particularly in China, wane with the timing of important events attracting foreigners, such as the Olympics or a large international business conference. In addition, hotels, which are typically the places where foreign visitors stay or work, and Internet service providers alter service and tweak routers in order to provide open access to visitors. This provides a very different experience of the country's Internet accessibility for foreign visitors compared to that of the average citizen.

A few countries have taken far more draconian measures. In North Korea, for example, Internet access is almost nonexistent, with only a few high-ranking government officials and foreign diplomats able to use it. Saudi Arabia has blocked more than 400,000 Web sites about religion, women's issues, Israel, and a slew of other topics. And Uzbekistan blocks all content centering on government corruption, criticism of the authoritarian regime, ethnic strife, and human rights.

Yet, what sometimes appears to be censorship is actually rooted in economics, Lih says. "Governments block certain services in order to give their own companies a competitive advantage," he notes. As a result, numerous YouTube and Twitter knockoffs exist in some countries, including China, and other countries block services such as Skype in order to protect government-run telephone services and other businesses.

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Breaching Censors' Walls

Increasingly, students, dissidents, journalists, bloggers, human rights advocates, and others are challenging Internet censorship. In the digital age, they're fighting back with an arsenal of tools such as proxy servers that circumvent filtering by masking the user and altering the way data flows to a Web server or by VPNs that tunnel through to other less censorious countries.

It's a cat-and-mouse game, to be sure. As individuals begin downloading and using proxy servers, it's common for government censors to detect the activity and block downloads, as well as the proxies. However, the same applications frequently become available at alternative sites and through peer-to-peer services. Moreover, new proxy servers continually spring up. But VPNs represent a different challenge, and most censoring countries are hesitant to block them because they're essential for commerce and used heavily by foreign business leaders and diplomats.

Some services, like Tor, a free program offered by the nonprofit Tor Project, circumvent censorship by routing communications across a distributed network of relays located around the world. These VPN tunnels make it possible to access blocked pages and sites, such as Facebook or YouTube. They also allow journalists and dissidents to publish Web sites and other services without revealing their location.

China, like many countries that practice Internet censorship, blocks Web sites sporadically and in no systematic way.

Another free VPN application, AnchorFree Hotspot Shield, enables users to view otherwise censored Web sites by converting the http protocol to an encrypted https protocol and providing users with a virtual identity. "Although the product was originally intended to serve as a universal privacy and security offering, a growing number of people are looking for a way to bypass controls and access information freely," says AnchorFree CEO David Gorodyansky.

Both Tor Project and AnchorFree's Web sites are blocked in China. Nevertheless, Gorodyansky claims that usage in China has doubled since the Chinese government began blocking the site last summer. Potential users download Tor and AnchorFree Hotspot Shield by visiting mirror sites or by sending the companies an email message and receiving a message with a Windows- or Mac-compatible file. In addition, individuals share applications with USB flash drives and through peer-to-peer services.

The battle over censorship is likely to intensify as the world becomes more Web-centric. Despite tools for piercing and circumventing firewalls, authorities are constantly searching for new and better ways to filter and block traffic, Lih notes. "The only reason that authorities aren't more aggressive in tracking down those who circumvent restrictions is that it simply isn't worth the trouble," he says. "There isn't a critical mass of population that's dangerous to the government."

* Further Reading

Deibert, R.J., Palfrey, J.G., Rohozinskiand, R., Zittrain, J. (Eds.)
Access Denied: The Practice and Policy of Global Internet Filtering, MIT Press, Cambridge, MA, 2008.

Fallows, J.
"The Connection Has Been Reset," The Atlantic, March 2008.

Farrar, L.
Cashing in on Internet censorship, CNN. com, February 19, 2010,

Reporters Without Borders
Enemies of the Internet, Reporters Without Borders, March 12, 2010,

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Samuel Greengard is an author and journalist based in West Linn, OR.

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UF1Figure. The headquarters of Google China before the search engine company exited the country earlier this year and started routing searches from China through its Hong Kong site.

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