AES and Modes of Operation

  1. ECB stands for
    (a) Electronic cipher Block
    (b) Electronic code Block
    (c) Electronic code Book
    (d) Electronic cipher Book

  2. Which among the following is not CPA secure?
    (a) ECB
    (b) CBC
    (c) CFB
    (d) None

  3. Which of the following are block ciphers?
    (a) ECB
    (b) CBC
    (c) CFB
    (d) All

  4. Which is the fastest mode of operation among four mode of operation?

  5. Which mode of operation is more secure?

  6. What is importance of Intialiczation Vector(IV) and CTR ?

  7. Why ECB is not CPA-secure and Why CBC is CPA-secure?

  8. Suppose IV is not random.Then is CBC and OFB mode both secure