An effort by China’s internet police to block “subversive” sites misfired and caused the massive internet blackout this week, which saw Chinese web traffic diverted to US servers owned by a company that has been critical of the Chinese government, the Washington Post reported on Thursday.
Experts have estimated that some 200 to 600 million internet users could not access any .com or .net websites for a period of three to eight hours. This made impossible any online activity, from money transfers to e-business transactions, to posting on social networks.
The users were instead diverted to a blank website, maintained on servers run by US-based Dynamic Internet Technology, a firm founded by anti-censorship activist Bill Xia, the newspaper said.
The censors – part of what is called the “Great Firewall of China” – usually block access to certain sites by redirecting traffic to fake or invalid IP addresses. But in Tuesday’s glitch, they sent the traffic to a Dynamic-linked IP address, the report said.
“The rule was supposed to be, ‘Block everything going to this IP address.’ Instead, they screwed up and probably wrote the rule as ‘Block everything by referring to this IP address’,” International Computer Science Institute researcher Nicholas Weaver was quoted as saying.
Another researcher, from Washington, noted seeing a similar glitches in Iran.
“This is what happens when you try to break the internet for censorship because things are going to go wrong and in catastrophic ways that bring down the internet or make it unusable. This is censorship backfiring,” the Washington Post quoted Collin Anderson, affiliated with the University of Pennsylvania, as saying.
The Chinese government, however, has insisted the glitch was a cyberattack , and that it was investigating who was behind it.
Some state reports also cast suspicion on the Falun Gong-linked Dynamic Internet Technology, claiming Xia’s company was responsible for the massive outage.
But both Dynamic and numerous experts on the mainland’s internet have laid the blame squarely on the Great Firewall.
“It all points to the Great Firewall. How that happened or why that happened, we’re not sure,” Xiao Qiang, an expert on the mainland’s internet controls based at the University of California, Berkeley, was quoted by Reuters as saying.
With additional reporting from Stephen Chen