Title of paper
Course Name
Instructor’s Name
Student Name
Date
Conventional Encryption
Question
You have been hired by a local company to consult with its security staff on encryption techniques. The staff has not been formally trained, so you will be demonstrating the principles of encryption through some simple exercises.
Use a 2-stage transposition technique to encrypt a message. The following information is what is needed to do this encryption:
Key: 2315746
Message: The transposition cipher technique works by permuting the letters of the plaintext. It is not very secure, but it is great for learning about cryptography (ignore the comma and the period in the message).
Prepare a Word document that explains this encryption technique. You should also include details as to how you arrived at your answer.
In addition, answer the following questions:
Is it possible to decrypt the message with a different key? Justify your answer.Do you agree with the statement of the message? Provide examples to support your view.
Be sure to reference all sources using APA format.
Solution
Stage 1: ignoring the comma, the period, and the spaces in the original message, we have the following string:
Thetranspositionciphertechniqueworksbypermutingthelettersoftheplaintextitisnotverysecurebutitisgreatforlearningaboutcryptography.
The key has 7 digits. Thus we prepare a table of 7 columns. Since the string above has 128 characters, our table will have 19 rows (128 / 7 = 18.28).
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Stage 2:XX XXX XXX XXX key XXXXXXX XX the permutation order XX XXXX XXX table XXXXXX by XXXXXX. The deciphered XXXX is XXXXXXXXX:
eoceeyiefiterifnuotsorqsueslttciaabphhpntubtloaivuttrotyathnrrteeensurlgratsicwpnttniresoitgnieikmhrpxoeteeaypriphoegthtsybgrncr
XXXXXXXXXX:
Is it possible XX decrypt the XXXXXXX with a different XXX? Justify XXXX answer.
No it is XXX possible. XXXXX, for a key of different size, XX don’t XXXX the XXXXX number of XXXXXXX XX reconstruct the table. XXXXXX, XXX a XXX XX the same XXXX (X in the example above) but different XXXXXXXXXXX, XX XXXX XXXX XXX wrong order XX fill out XXX table. Therefore the XXXXXXXXX message XXXXXX be XXXXXXXXX decrypted.
Do you XXXXX XXXX the XXXXXXXXX XX XXX message? XXXXXXX examples XX XXXXXXX XXXX XXXX.
The XXXXXXXXX is XXXXXXX that the deciphered text XX just a XXXXXXXXXXX of XXX XXXXXXXX message. XXX XXX XXXX, XXXXXXXX an XXXXXXX to XXXXXXX XXX XXXXXXX “XXXXXXXXXXXXXXXXXXXXXXXXXX” with XXX same XXX XXXXXXX. We XXXX the XXXXXXXXX table:
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XXX XXXXXXXXX XXXXXXX XX thus: “cjqxahovbipwfmtdkrygnuelsz”, XXXXX is a XXXXXXXXXXX of letters in the plain XXXX.