Understanding Techniques for Hiding and Scrambling Information

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Goals

• Understand steganography
• Use steganography
• Detect steganography
• Understand basic cryptography
• Utilize basic cryptography
• Understand general cryptanalysis techniques

Steganography

• Steganography

Encryption

• History of Cryptography
• Kerckhoff’s Principle

Symmetric Cryptography

• Feistel Function
• Data Encryption Standard (DES)
• Advanced Encryption Standard (AES)
• Other symmetric algorithms
  • Blowfish
  • Serpent
  • Skipjack
• Cryptographic Hash

Asymmetric Cryptography

• RSA
• Diffie-Hellman
• Other asymmetric algorithms
  • MQV
  • Elliptic Curve
  • DSA

Breaking Encryption

• Cryptanalysis
  • Frequency Analysis Attack
  • Kasiski Examination
  • known plaintext
  • chosen plaintext
  • ciphertext only
  • key-related attack

Quantum Computing and Cryptography

• quantum computing is based on using quantum state bits, or qubits
  • can be polarization of a photon, energy level of an electron, or other quantum state
• suffer from problem of decoherence
  • can only maintain state for short period of time
• once issues resolved, asymmetric algorithms based on prime factors and discrete logarithms will no longer be secure
• NIST is working on a quantum-resistant cryptographic standard