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CAP Cryptographic Analysis Program

CAP Cryptographic Analysis Program. Breaking a Double Column Transposition Cipher Help Presentation. Press Enter or click on your mouse button to continue. Cryptanalysis of a DT.

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CAP Cryptographic Analysis Program

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  1. CAPCryptographic Analysis Program Breaking a Double Column Transposition Cipher Help Presentation Press Enter or click on your mouse button to continue

  2. Cryptanalysis of a DT A weakness of the double column transposition cipher lies in the use of the same pair of keys on several plaintext messages all of the same size. For example, if the following 4 messages between Bob and Alice were intercepted: etmai atecb bsbnq xivjb eecqu heikn oxlct sedwn oowqq texda aqmue caeon ioox panbt tjliu eeyhq xotbi dttqy dwbml bxooa oweal hoaqp nexbh tqaut iekau wocx monat rtwle bocoq xhofb aurqe oxino oxlir defar uhoqe mexbn nqttn cgwoo rtox awsbe lymtt ernrq xtnei olfqt lebne uxorb okorl ocmqf iexru oqwhe oogao aacx

  3. Process • Place all 4 messages “in depth” – that is one on top of the other • Treat it as a large anagramming problem etmai atecb bsbnq xivjb eecqu heikn oxlct sedwn oowqq texda aqmue caeon ioox panbt tjliu eeyhq xotbi dttqy dwbml bxooa oweal hoaqp nexbh tqaut iekau wocx monat rtwle bocoq xhofb aurqe oxino oxlir defar uhoqe mexbn nqttn cgwoo rtox awsbe lymtt ernrq xtnei olfqt lebne uxorb okorl ocmqf iexru oqwhe oogao aacx Columns of “x” should all go to the end

  4. Using CAP • CAP provides a special anagramming tool for Double Column Transpositions:

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