CYG Chapter 2 Classical Cryptography
Questions about the lecture 'Cryptography' of the RWTH Aachen Chapter 2 Classical Cryptography
Questions about the lecture 'Cryptography' of the RWTH Aachen Chapter 2 Classical Cryptography
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| Karten | 47 |
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| Sprache | English |
| Kategorie | Informatik |
| Stufe | Universität |
| Erstellt / Aktualisiert | 21.03.2017 / 12.11.2017 |
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Who used the technique?
[scytale.classical]
Spartans around 400 BC
What is the tool?
[scytale.classical]
Wand with diameter d (So-called scytale)
How does the encryption works?
[scytale.classical, 3]
1. Blank stripe is wrapped around the wand
2. Letters of message are written column wise
3. Unwrapping the strip leaves a meaningless message
How does the decryption works?
[scytale.classical]
Use wand with same diameter d
What are the tools?
[substitution.classical, 2]
1. Alphabet Sigma={x1,…,xm}
2. Permutation pi \in Sm of {1,…,m}
How does the encryption works?
[substitution.classical]
Substitute letter xi by xpi(i) in the plain-text
How does the decryption works?
[substitution.classical]
Substitute letter xj by xpi’(j) in the cipher-text
What are the variants?
[substitution.classical, 2]
1. Caesar and 2. affine in Zm
