CS372: Solutions for Homework 15

Problem 1:

Suppose machine A encrypts a file using machine A's private key and sends the encrypted file to machine B. Which of the following guarantees does this strategy provide?
  1. Secrecy (no one but B could read this message)
  2. Authentication (no one but A could send this message)
  3. Both secrecy and authentication
  4. Neither secrecy nor authentication

Solution: Needs solution.

Problem 2:

True/False. Interception of encrypted bank ATM PINs as they are transmitted over telephone wires is one of the top three sources of fraudulent bank ATM withdrawals.

Solution: False.

Problem 3:

2-factor authentication is an alternative to passwords. Give an example of 2-factor authentication and explain its advantages compared to passwords.

Solution: Needs solution.