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Chris Christensen Northern Kentucky University. Lester S. Hill 1890 - 1961.

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Presentation on theme: "Chris Christensen Northern Kentucky University. Lester S. Hill 1890 - 1961."— Presentation transcript:

1 Chris Christensen Northern Kentucky University

2 Lester S. Hill 1890 - 1961

3 Simple SubstitutionDigraphic Substitution Plaintext cipher Ciphertext MVHQLU

4 Plaintext mis sis sip pik Ciphertext BQT SEI AEP YFC

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7 2 October 192613 November 1926

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10 Plaintext comehere stayaway

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12 Enciphering KeyDeciphering Key

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18 Enciphering Key Deciphering Key

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20 Lester Hill’s Cipher Is a true block cipher.Blends two messages together. Can encipher a true and false message and, if forced to reveal “the message,” choose to reveal the false message. Jack Levine’s Cipher

21 THEDEPARTMENTOFMATHEMATICSA TNORTHERNKENTUCKYUNIVERSITY

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