JAVA Cryptography

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JAVA Cryptography
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Encryption method

• Symmetric Key
• DES
• 3DES
• AES
• Asymmetric Key
• DSS
• RSA

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Symmetric Key

• Secret key
• Block Algorithms
• Stream Algorithms

Insecure Channel
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Asymmetric Key

• Public Key
• Private Key

Insecure Channel
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Example
A
B
Plain Text
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DES

• Data Encryption Standard (DES)
• Encryption Key
• 64 bits data block
• 56 bits key length
• 8 bits parity
• Developed from FeistelChipher (Iterated Block
  Chipher) 16 times
• WEAK brute force attack

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DES Algorithm
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DES Mode

• ECB Mode Electronic Code Book
• CBC Mode Cipher Block Chaining

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Triple-DES

• Encryption Key
• 3DES 56x3 168 bits key length
• Algorithm
• encryption using DES with the first 56-bit key
• decryption using DES with the second 56-bit key
• encryption using DES with the third 56-bit key

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Rijndael (AES)

• Rijndael (Vincent) Rijmen (Joan) Daemen In
  year 1998
• Data block 128 bit
• Key length 128, 192, 256 bit
• Encrypt 10, 12, 14 Rounds depend on key length
• Algorithm Substitution-Permutation Network
• WEAK Side Channel Attack