An Internet outage in China that cut access for hundreds of millions of people may have been the unintended result of changes made to government web controls.
More than two-thirds of web traffic in a country with more than 618 million Internet users was disrupted on Jan. 21, according to the online security provider Qihoo 360 Technology Co. Affected sites included those of Alibaba Group and Baidu Inc. China said hackers may have been to blame.
The group Greatfire.org, which monitors censored posts on the Internet, said it had evidence the outage was caused by the censorship network in China. The disruption may have been the result of a hacker attack, an attempt to block an Internet Protocol address or censors adding new rules to upgrade their controls, according to a statement on its website.
China routinely censors the Internet by blocking access to websites with content critical of the Communist Party’s rule. Websites such as Twitter, Facebook. and Youtube are inaccessible in China. China’s National Computer Network Emergency Response Center in China said it had come to the preliminary conclusion that the outage was caused by a cyber-attack, according to a statement on its website yesterday.
The probability that the failure was caused by hacking attempts to contaminate domain name system servers is low, said Lento Yip, chairman of Hon Kong Internet Service Providers Association.
“You cannot hack all the DNS servers in China,” Yip said by phone. “If it was DNS contamination it should have been isolated, it should have been a few cases instead of the whole Internet becoming inaccessible.”
Much of China’s web traffic during the outage was directed to an Internet address owned by Dynamic Internet Technology Inc. The group was founded by a member of the Falun Gong religious sect, which is banned in China.
China’s top-level domain root server with the .cn country code wasn’t affected, the China Internet Network Information Center said in an e-mailed statement on Jan. 22. Sites with the .cn code originate in China. The center declined to comment on the Greatfire.org report in an e-mailed response to questions.
Users had problems accessing websites including those run by Baidu and Alibaba, according to Li Tiejun, a security engineer at Kingsoft Corp. Aliyun, a website of Alibaba’s that provides cloud services, posted on its official microblog at 4:38 p.m. Beijing time on Jan. 21 that its service was in the process of recovery.
Kaiser Kuo, a spokesman for Baidu, said in an e-mail yesterday some users couldn’t access websites around 3 p.m. the day before and that engineers were restoring the service.