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SYMMETRIC CRYPTOSYSTEMS Symmetric Cryptosystems 10/06/2015 | pag. 2
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Block Ciphers: Classical examples Symmetric Cryptosystems 10/06/2015 | pag. 3 Affine Cipher Affine Linear and Linear Cipher Vigenère Hill We needed some linear algebra!
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Affine Cipher Symmetric Cryptosystems 10/06/2015 | pag. 4
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Example: Cryptanalysis of the Affine Cipher Symmetric Cryptosystems 10/06/2015 | pag. 5
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Intermezzo: Matrices over Rings Cryptography 10/06/2015 | pag. 6
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Intermezzo: Invertible Matrices Cryptography 10/06/2015 | pag. 7
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Intermezzo: Invertible Matrices Cryptography 10/06/2015 | pag. 8
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Intermezzo: Invertible Matrices Cryptography 10/06/2015 | pag. 9
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Intermezzo: Invertible Matrices Cryptography 10/06/2015 | pag. 10
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Intermezzo: Affine Linear Functions Cryptography 10/06/2015 | pag. 11
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Intermezzo: Affine Linear Functions Cryptography 10/06/2015 | pag. 12
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Affine Linear Cipher Cryptography 10/06/2015 | pag. 13
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Affine Linear Cipher Cryptography 10/06/2015 | pag. 14
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Example: Affine Linear Cipher - Vigenère Cryptography 10/06/2015 | pag. 15
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Example: Linear Cipher - Hill Cryptography 10/06/2015 | pag. 16
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Example: Linear Cipher – Permutation Cipher Cryptography 10/06/2015 | pag. 17
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Cryptanalysis of the Affine Linear Cipher Symmetric Cryptosystems 10/06/2015 | pag. 18
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Cryptanalysis of the Affine Linear Cipher Symmetric Cryptosystems 10/06/2015 | pag. 19
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Cryptanalysis of the Affine Linear Cipher Symmetric Cryptosystems 10/06/2015 | pag. 20
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Example: Cryptanalysis of the Affine Linear Cipher Symmetric Cryptosystems 10/06/2015 | pag. 21 FUSS.
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Block Ciphers: Remark Secure block ciphers must not be (affine) linear or easy to approximate by linear functions!!! Cryptography 10/06/2015 | pag. 22
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Block Ciphers: Remark Cryptography 10/06/2015 | pag. 23 Implementation of a (non-linear!) substitution in a block cipher often occurs through a look-up table, called S-box.
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Block Ciphers: Advanced examples Symmetric Cryptosystems 10/06/2015 | pag. 24 DES – Feistel Cipher AES – Rijndael
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DES Cryptography 10/06/2015 | pag. 25
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DES: Feistel Cipher Cryptography 10/06/2015 | pag. 26 An iterated block cipher is a block cipher involving the sequential repetition of an internal function called rounds. (iterated)
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DES: Feistel Cipher Cryptography 10/06/2015 | pag. 27
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DES: Feistel Cipher Cryptography 10/06/2015 | pag. 28
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DES: Algorithm Cryptography 10/06/2015 | pag. 29
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DES: Algorithm Cryptography 10/06/2015 | pag. 30
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DES: Algorithm Cryptography 10/06/2015 | pag. 31
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DES: Algorithm Cryptography 10/06/2015 | pag. 32
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DES: Algorithm Cryptography 10/06/2015 | pag. 33
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DES: Algorithm Cryptography 10/06/2015 | pag. 34
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DES: Algorithm Cryptography 10/06/2015 | pag. 35
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DES: Algorithm Cryptography 10/06/2015 | pag. 36
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DES: Algorithm Cryptography 10/06/2015 | pag. 37
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DES: S-Boxes Cryptography 10/06/2015 | pag. 38
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DES: Algorithm Cryptography 10/06/2015 | pag. 39
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DES: Algorithm Cryptography 10/06/2015 | pag. 40
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DES: Algorithm Cryptography 10/06/2015 | pag. 41
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DES: Algorithm Cryptography 10/06/2015 | pag. 42 Round number Number of left rotations 11 21 32 42 52 62 72 82 91 102 112 122 132 142 152 161
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DES: Algorithm Cryptography 10/06/2015 | pag. 43
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DES: Algorithm Cryptography 10/06/2015 | pag. 44
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DES: Algorithm Cryptography 10/06/2015 | pag. 45
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Example: DES Key Cryptography 10/06/2015 | pag. 46 Conversion Code - Chart DECI MAL 0123456789101112131415 HEX0123456789ABCDEF BINA RY 0000000100100011010001010110011110001001101010111100110111101111
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Example: S-Box Cryptography 10/06/2015 | pag. 47
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Example: DES Cryptography 10/06/2015 | pag. 48
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Example: DES Cryptography 10/06/2015 | pag. 49
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Example: DES Cryptography 10/06/2015 | pag. 50
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Example: DES Cryptography 10/06/2015 | pag. 51
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