A group of Canadian human-rights activists and computer security researchers has discovered a huge surveillance system in China that monitors and archives certain Internet text conversations that include politically charged words.
The system tracks text messages sent by customers of Tom-Skype, a joint venture between a Chinese wireless operator and eBay, the Web auctioneer that owns Skype, an online phone and text messaging service.
The discovery draws more attention to the Chinese government’s Internet monitoring and filtering efforts, which created controversy this summer during the Beijing Olympics.
Researchers in China have estimated that 30,000 or more “Internet police” monitor online traffic, Web sites and blogs for political and other offending content in what is called the Golden Shield Project or the Great Firewall of China.
The activists, who are based at Citizen Lab, a research group that focuses on politics and the Internet at the University of Toronto, discovered the surveillance operation last month. They said a cluster of eight message-logging computers in China contained more than 1 million censored messages. They examined the text messages and reconstructed a list of restricted words.
The list includes words related to the religious group Falun Gong, Taiwan independence and the Chinese Communist Party, the researcher said. It includes not only words like democracy, but also earthquake and milk powder.
The list also serves as a filter to restrict text conversations. The encrypted list of words inside the Tom-Skype software blocks the transmission of those words and a copy of the message is sent to a server.
The Chinese servers retained personal information about the customers who sent the messages. They also recorded chat conversations between Tom-Skype users and Skype users outside China. The system recorded text messages and Skype caller identification, but did not record the content of Skype voice calls.
In just two months, the servers archived more than 166,000 censored messages from 44,000 users, said a report that was published on the Information Warfare Monitor Web site at the university.
The researchers were able to download and analyze copies of the surveillance data because the Chinese computers were improperly configured, leaving them accessible. The researchers said they did not know who was operating the surveillance system, but they said they suspected that it was a Chinese wireless firm, possibly with cooperation from Chinese police.
Independent executives from the instant-message industry say the discovery is an indication of a spiraling computer war that tracks new forms of communications technologies.
“I can see an arms race going on,” said Pat Peterson, vice president for technology at Cisco’s Ironport group, which provides messaging security systems. “China is one of the more wired places of the world and they are fighting a war with their populace.”
The Chinese government is not alone in its Internet surveillance efforts. In 2005, the New York Times reported that the US National Security Agency was monitoring large volumes of telephone and Internet communications flowing into and out of the US as part of an eavesdropping program intended to hunt for evidence of terrorist activity.
The researchers said their discovery contradicted a public statement made by Skype executives in 2006 after the content filtering of the Skype conversations was reported. At the time the company said that the conversations were protected and private.