According to a recent report conducted by University of Toronto, Harvard, Oxford and Cambridge, 26 of 40 countries surveyed utilize some degree of state-sponsored software filtering.

China, Iran, Syria, Tunisia, Vietnam, Uzbekistan, Oman, Pakistan, Saudi Arabia, Sudan, the United Arab Emirates, Jordan, Morocco, and Singapore were mentioned as countries actively filtering its citizens.

The study found that many of the Middle Eastern countries mainly filtered international news.  Saudi Arabia focuses its censorship on political sites, pornography and gambling.  Tunisia also focuses their filter on pornography and sites that dealt with human rights and political opposition to the government. 

South Korea enabled filters to eliminate North Korean web sites.  Thailand, while not in the report, recently filtered YouTube and other video-sharing websites that disseminated videos critical of the country's king.

According to the University of Toronto report, Russia, Venezuela, Egypt, Hong Kong, Israel and Iraq were among the countries found that did not enable any sort of state-sponsored of content filtering.

SmartFilter, developed by Secure Computing in San Jose, California, is one of the more popular software filtering tools found used today.  Saudi Arabia, the United Arab Emirates, Oman, Sudan and Tunisia are currently using this software.

Other countries simply display a default page or  a DNS error in an attempt to mask that any censorship is taking place. China, by far the worst offender according to the report, recently censored the entire LiveJournal network in an attempt to block individual blogs.

A brief lax in the Great Firewall of China resulted in major headlines last year.  For a six hour period, all users inside China were able to view and search for content typically deemed unviewable by the Chinese government.  The Chinese government, Skype and Google have since declared it their right to continue to censor and promote censorship as a cost of doing business in such countries. Last year Yahoo! spoke openly against censorship in China, yet only a month later it was discovered that Yahoo! is one of the most censored western portals inside China.

"Once the tools are in place, authorities realize that the Internet can be controlled. There used to be a myth that the Internet was immune to regulation. Now governments are realizing it's actually the opposite," said associate professor of political science at the University of Toronto, Ron Deibert.

The report did not include western countries, citing North American censorship typically takes place because of copyright infractions.  None of the 40 countries observed during the analysis incorporated any filtering based on intellectual property concerns.