Three ASCII messages containing English letters and spaces only are encrypted using the one-time pad and the same key. The 10th byte of the first ciphertext is observed to be 0x66, the 10th byte of the second ciphertext is observed to be 0x32, and the 10th byte of the third ciphertext is observed to be 0x23. Let m1 (resp., m2, m3) denote the 10th ASCII character in the first (resp., second, third) message. What is the most you can conclude about m1, m2, and m3?

For the byte-wise shift cipher where the key space is {0, …, 255}. What is Pr[K = 2]?

Which of the following problems is hard if the RSA assumption holds? In all the below, N is a product of distinct, large primes p and q, and e is relatively prime to ϕ(N).

What is the value (in decimal) of 0x48?

If the message “cryptoisfun” is encrypted with the shift cipher and key 25. What is the resulting ciphertext?

Which of the following is a drawback of the private-key setting that is NOT addressed by the public-key setting?

Assume we want to use a hash function with output length as small as possible, subject to being collision resistant against a birthday attack running in time 2192. Which hash function would be the best choice?

In which of the following settings is naive application of private-key cryptography applicable? (Check all that apply.)

Question 13 (3 points) In a thoughtful paragraph, argue that one or one part of a second group project (case study) represents elements that mirror or complement things we’ve studied in Module 3 (e.g. location/social capital, parental advantage, and/or changes in the nature of work).

Question 12 (3 points) In a thoughtful paragraph, argue that one or one part of one of group project (case study) represents elements that mirror or complement things we’ve studied in Module 3 (e.g. location/social capital, parental advantage, and/or changes in the nature of work).