TERMIUM Plus®
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POLYALPHABETIC SUBSTITUTION [3 records]
Record 1 - internal organization data 1997-12-15
Record 1, English
Record 1, Subject field(s)
- IT Security
Record 1, Main entry term, English
- index of coincidence
1, record 1, English, index%20of%20coincidence
correct
Record 1, Abbreviations, English
Record 1, Synonyms, English
Record 1, Textual support, English
Record number: 1, Textual support number: 1 DEF
... a statistical measure of text which distinguishes text encrypted with a simple substitution cipher(also known as a monoalphabetic cipher) and more complicated Vigenere methods(polyalphabetic ciphers.) It was discovered by Phillip Friedman... To determine the index of coincidence of a piece of text, take the text and shift it by some random number of places(wrapping around if necessary) and write the shifted and unshifted texts next to each other... 1, record 1, English, - index%20of%20coincidence
Record 1, Key term(s)
- index des coincidences
Record 1, French
Record 1, Domaine(s)
- Sécurité des TI
Record 1, Main entry term, French
- index de coïncidence
1, record 1, French, index%20de%20co%C3%AFncidence
masculine noun
Record 1, Abbreviations, French
Record 1, Synonyms, French
Record 1, Textual support, French
Record 1, Key term(s)
- index des coïncidences
Record 1, Spanish
Record 1, Textual support, Spanish
Record 2 - internal organization data 1988-03-11
Record 2, English
Record 2, Subject field(s)
- Intelligence (Military)
- Handwriting Analysis and Cryptography
Record 2, Main entry term, English
- double-key substitution
1, record 2, English, double%2Dkey%20substitution
correct
Record 2, Abbreviations, English
Record 2, Synonyms, English
- polyalphabetic substitution 1, record 2, English, polyalphabetic%20substitution
correct
- double substitution 1, record 2, English, double%20substitution
correct
Record 2, Textual support, English
Record number: 2, Textual support number: 1 OBS
Most modern substitution ciphers are of the "double-substitution" type, in which a different cipher alphabet is used to encipher each successive letter of the clear text. 1, record 2, English, - double%2Dkey%20substitution
Record 2, French
Record 2, Domaine(s)
- Renseignement (Militaire)
- Graphologie et cryptographie
Record 2, Main entry term, French
- substitution à double clef
1, record 2, French, substitution%20%C3%A0%20double%20clef
correct, feminine noun
Record 2, Abbreviations, French
Record 2, Synonyms, French
- double substitution 2, record 2, French, double%20substitution
correct, feminine noun
- substitution double 3, record 2, French, substitution%20double
correct, feminine noun
Record 2, Textual support, French
Record number: 2, Textual support number: 1 DEF
substitution dans laquelle chaque lettre (unité de chiffrement) est chiffrée à l'aide de deux clefs : une clef simple de substitution (clef de rang); une clef déterminant l'ordre d'emploi de cette clef simple de substitution (clef principale). 1, record 2, French, - substitution%20%C3%A0%20double%20clef
Record 2, Spanish
Record 2, Textual support, Spanish
Record 3 - internal organization data 1987-01-16
Record 3, English
Record 3, Subject field(s)
- Intelligence (Military)
Record 3, Main entry term, English
- Beaufort cipher 1, record 3, English, Beaufort%20cipher
Record 3, Abbreviations, English
Record 3, Synonyms, English
Record 3, Textual support, English
Record number: 3, Textual support number: 1 DEF
A system of polyalphabetic substitution equivalent to Vigenère cipher with a reversed normal cipher sequence, the keying formula of which is P + C=K. 1, record 3, English, - Beaufort%20cipher
Record 3, French
Record 3, Domaine(s)
- Renseignement (Militaire)
Record 3, Main entry term, French
- procédé Beaufort
1, record 3, French, proc%C3%A9d%C3%A9%20Beaufort
masculine noun
Record 3, Abbreviations, French
Record 3, Synonyms, French
Record 3, Textual support, French
Record 3, Spanish
Record 3, Textual support, Spanish
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