Objective:

  • Present an overview of the main concepts of symmetric cryptography.
  • Explain the difference between cryptanalysis and brute-force attack.
  • Summarize the functionality of DES.
  • Present an overview of AES.
  • Explain the concepts of randomness and unpredictability with respect to random numbers.
  • Understand the differences among true random number generators, pseudorandom number generators, and pseudorandom functions.
  • Present an overview of stream ciphers and RC4.
  • Compare and contrast ECB, CBC, CFB, and counter modes of operation.
  • Assignment
  • 2.1 What are the essential ingredients of a symmetric cipher?
  • 2.2 What are the two basic functions used in encryption algorithms?
  • 2.3 How many keys are required for two people to communicate via a symmetric cipher?
  • 2.4 What is the difference between a block cipher and a stream cipher?
  • 2.5 What are the two general approaches to attacking a cipher?
  • 2.6 Why do some block cipher modes of operation only use encryption while others use both encryption and decryption?
  • 2.7 What is triple encryption?
  • 2.8 Why is the middle portion of 3DES a decryption rather than an encryption?
  • Complete your answers on a WORD Document.