Here's a description from two years ago:January 23, 2006: There's a Cyber War going on between China and the rest of the world. The problem is, there's enough proof to know that China is behind an increasing number of Internet based attacks, but not enough to call China out on it. It began about five years ago, with an increasing number of very well executed Internet attacks that appeared to be coming from China. At first, it was thought to be adventurous computer science students, or criminals out to steal something they could sell.
Then, in 2003, came the "Titan Rain" incident. This was a massive and well organized attack on American military networks. The people carrying out the attack really knew what they were doing, and thousands of military and industrial documents were sent back to China. The attackers were not able to cover their trail completely, and some of the attackers were traced back to a Chinese government facility in southern China.
The Chinese government denied all, and the vast amounts of technical data American researchers had as proof was not considered compelling enough for the event to be turned into a major media or diplomatic event.
There's
more at that page, and a search for "Titan Rain" will provide more information.
An update (an article published today):
India, too, is under cyberattack from China, and is reacting to it. (Look for "Great Wall of India".)
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