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    SIS Makes Breakthrough Against Japanese Code (20 SEP 1940)

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    SIS Makes Breakthrough Against Japanese Code (20 SEP 1940)

    On 20 September 1940, Genevieve Grotjan, a 27-year-old statistician, discovered a pattern in several Japanese ciphered messages. The discovery provided an entry point that led to one of the greatest achievements in cryptanalysis: the breaking of Japan’s highest-level diplomatic cipher system, often referred to as PURPLE.

    IMAGE INFO

    Date Taken: 09.20.2023
    Date Posted: 09.22.2023 10:49
    Photo ID: 8036321
    VIRIN: 230920-O-MF537-6723
    Resolution: 750x960
    Size: 177.49 KB
    Location: US

    Web Views: 17
    Downloads: 1

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