Cyberwarfare: A Chinese ghost in the machine? Identifying the perpetrator of cyber-attacks can be impossible

Cyberspace is ideal for spies. Digitally disguised and undeterred by borders or passports, they can pick locks anywhere in the world, pilfer secrets without trace and even leave toxic traps for the unwary.Security chiefs are very worried; NATO’s new cyberwarfare think-tank in Estonia gets requests for help from across the world. And for researchers outside the charmed circle of high-security clearance, establishing hard evidence of mischief on the net is even harder.
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