Response | Technology cont’d

• Cryptography

  • Motivation
    • Protecting information by ensuring its integrity and confidentiality... even as it travels over untrusted networks
    • Includes authentication and non-repudiation services... digital signatures for example
  • Private-key encryption
    • Requires sender and receiver to share the same key... exchanging it before exchanging information
    • Relatively fast
    • Ex: DES, IDEA, RC2, RC4, RC5, Blowfish
  • Public-key encryption
    • Uses key pairs (mathematically-related)
      • Public portion published
      • Private portion kept secret
    • Doesn’t require senders and receivers to exchange private keys first
    • Much slower than private-key