The 1944 Bletchley Park Cryptographic DictionaryPage 29 |
Tony Sale's Codes and Ciphers |
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DIFFERENCE, v :
2. To subtract a length of subtractor key, esp. of letter-subtractor machine key, from itself at the interval of one of the basic components (or wheels) in order to eliminate the component whose period is that interval, as a step in key-analysis or key-breaking.
3. To subtract two cipher texts (produced by a letter-subtractor machine) which are in depth with each other, the one from the other, thereby eliminating the key and obtaining the difference of the two clear texts, as a step in reading a depth of two messages, by the stencil-search method.
4. To subtract a cipher text from itself, usually at an interval of one, as e.g. in Tutte's method.
DIFFERENCE BOOK :
DIFFERENCE PAPER :
DIGRAPHIC :
DILLYISMUS :
DINGY, a :
DINGY n :
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