With independent media blocked from reporting on recent demonstrations in Iran after Friday's election, many people around the world turned to the micro-blog service Twitter for a detailed account of events in Tehran and other Iranian cities.

But if the Iranian government so chose, it could attempt to cut off Iranians' direct access to Twitter and other social media services to prevent the spread of information, according to Yaman Akdeniz, director of the UK-based Cyber-Rights.org.

"Undemocratic countries like Iran rely on crude blocking and filtering mechanisms to limit their citizen's usage of the Internet temporarily, or indefinitely," he said. "The true extent of the Internet censorship attempts in Iran remains to be seen."

Tehran blocked the popular networking site Facebook for two days before the elections and only restored access after a massive public outcry. Since the elections, authorities have attempted to deny access to several pro-opposition Web sites and news portals likely to challenge current President Mahmoud Ahmadinejad's announced victory, according to the media rights group Reporters Without Borders.

Anonymous Web surfing

There are, however, technical ways for Iranians - and others living under repressive regimes that filter the Internet - to access all the material on the World Wide Web, according to Akdeniz.

"However hard the governments try, total censorship and control will not be achieved on the Internet," he added. "Going back to the topic, the Iranians will find ways and means of accessing the Internet, regardless of their government's crude attempt to control the free flow of information."

Computers outside the country filtering the Web can be set up as so-called proxy servers, which pass along information from one Internet connection to another like an anonymous virtual messenger whose presence doesn't tip off security authorities.

Reporters Without Borders has for years encouraged cyber-dissidents to make use of such proxy services, including the popular program Tor, which passes data through a random series of three computers before it arrives at its destination.

Mirroring Internet traffic

The program, which builds a network of currently about 2,000 volunteers who act as online go-betweens, allows, for example, an Iranian to see otherwise blocked sites by encrypting and routing his request through a series of three random computers with access to the entire Web, then sending the data they acquire back through the same anonymous network, explains Andrew Lewman, the executive director of the Tor Project.

"Someone watching the Internet would not be able to track who you are and where you are going," he said, adding that the number of Tor connections from Iran has doubled since last week's election, moving the nation up the Tor user list from near the bottom 50 to within the top 15 of the some 500,000 people using Tor each day,

More people using the network, regardless of their location or what they're doing on the Web, makes Tor more effective at making the Internet anonymous, Lewman said, adding that the service is simple to install and wouldn't work if only activists and dissidents used the program.

"The more normal people who turn on a connection on their home computer the better, because then it looks more and more like the general Internet," he said. "If Tor becomes an activists' network and anyone watching would say, 'That's an activist network connection; we should watch that.'"

Proxy critics remain

Despite the protection proxy services offer those living under oppressive governments, the system does have some detractors. Critics say the network can be taken advantage of by terrorists and other criminals. That's an argument Lewman said isn't as persuasive as it may seem.

"Criminals have far better anonymity and privacy than most likely anyone in the world," he said. "If you're already willing to break the law, then you can do far more private things. If you steal a person's identity on the Internet you'll have more anonymity than any tool can provide."

While Tor and other tools can help Web users get around the blocks and filters governments put on the Internet, they should not be seen as the final answer in the fight to stop online censorship, according to Akdeniz.

"Circumvention technologies provide only a partial solution to the problem of Internet censorship," he said. "Unless there is a process towards democratization and openness, censorship will be the norm."

Author: Sean Sinico

Editor: Susan Houlton