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

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Presentation transcript:

Chris Christensen Northern Kentucky University

Lester S. Hill

Simple SubstitutionDigraphic Substitution Plaintext cipher Ciphertext MVHQLU

Plaintext mis sis sip pik Ciphertext BQT SEI AEP YFC

2 October November 1926

Plaintext comehere stayaway

Enciphering KeyDeciphering Key

Enciphering Key Deciphering Key

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

THEDEPARTMENTOFMATHEMATICSA TNORTHERNKENTUCKYUNIVERSITY