Intro to Crypto

Question 1

If the only form of attack that that could be made on an algorithm is brute-force, then the way to counter such attacks would be to ______________

Answer 1

use a longer key lengthP2 L5

Question 2

What weaknesses can be exploited in the Vigenere cipher

Answer 2

It uses repeating key letters,The length of the key can be determined using frequency analysisP2 L5

Question 3

Which of the following characteristics would improve password security?A) Use a one-way hash functionB) Should not use the avalanche effectC) Should only check to see that the hash function output is the same as stored output

Answer 3

A) Use a one-way hash functionC) should only check to see that the hash function output is the same stored outputP2 L5

Question 4

Attack:A method to determine the encryption function by analyzing known phrases and their encryption

Answer 4

linear cryptanalysisP2 L5

Question 5

Attack:Analyzing the effect of changes in input on the encrypted output

Answer 5

differential cryptanalysisP2 L5

Question 6

Attack:Compare the cipher texts with its known plaintext

Answer 6

chosen-plaintext attacksP2 L5

Question 7

Attack:A method where a specific known plaintext is compared to its ciphertext

Answer 7

Known-plaintext attacksP2 L5

Question 8

Asymmetric encryption is better for:A) provide confidentiality of a messageB) securely distribute a session keyC) scalability

Answer 8

B) securely distribute a session keyC) scalabilityP2 L5

Question 9

Symmetric encryption can only be used to provide confidentiality

Answer 9

falseP2 L5

Question 10

Public-key encryption can be used to create digital signatures

Answer 10

trueP2 L5

Question 11

Cryptanalytic attacks try every possible key on a piece of ciphertext until an intelligible translation into plaintext is obtained

Answer 11

falseP2 L5

Question 12

The secret key is input to the encryption algorithm

Answer 12

trueP2 L5