Cryptographers Achieve Perfect Secrecy With Imperfect Devices

In Ian Fleming’s first novel, James Bond returns from the Royale-les-Eaux casino to his hotel room and inspects it for signs of intrusion. First, he confirms that a hair carefully placed inside his writing desk has not been moved. He then checks that talcum powder on a cupboard handle is free of fingerprints. Lastly, he confirms that the water level in the lavatory water cistern hasn’t changed.

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