Watson Research Centre in New York state by a team led by Steve White, is called the Digital Immune System.

ECONOMIST: A thousand ills require a thousand cures

They are also robust, fault-tolerant and able to respond quickly to an intruder all qualities that are desirable in a digital immune system, too.

ECONOMIST: A thousand ills require a thousand cures

The Digital Immune System works like this.

ECONOMIST: A thousand ills require a thousand cures