April 15, 2012
At approximately 11am local time yesterday, Internet users around China reported significantInternet blackouts . Not only were they unable to access some Chinese sites, but also many foreign Web sites that had not previously been blocked.
The issue was not isolated to China. Web users in Hong Kong and Japan also reported issues with accessing Chinese sites. A number of explanations immediately came to light, with the most viable cause being the 8.7 magnitude earthquake  in Indonesia on Wednesday, that might have damaged undersea cables.
However, reports from China’s major telecommunication companies  — China Telecom and Unicom — suggest that this was not the case. China Telecom confirmed that the earthquake had not interfered with the underwater cables in any way.
Both companies also shot down theories that the outage could have been caused by some sort of blip in the system, with Telecom insisting that there was no issue with their network. As all Chinese Internet traffic passes through the two networks’ infrastructure to get overseas, this had seemed like a likely culprit.