TU Wien:Network Security VU (Zseby)/Exam 2018-04-24 (SS18)

16 questions on 9 pages, 1 hour of time

1) What is the difference between viruses and worms?

2) Explain SYN floods

3) Can you use only Letter Frequencies analysis on only transposition cipher to get info about plaintext.

4)

5) One-Time-Pad Characteristics? 2 given: only use once, key remains secret. 2 missing for answer: key should be random, key lenght is same as message lenght.

6) One-Time Pad, key given, m1, m2 given. what info can you get about m1,m2 when you encrypt with same key. Answer: m1 was inverse of m2

7)

8) ECC Graph, Addition of 2 Points P and Q. Show result R of Addition in the graph. (Slide 04 / 66)

9) Explain the only ciphertext attack.

10) What are the encryption and decryption functions for RSA?

11) Can you prove that a message signed from Bob (RSA) is valid (e.g. at court) ?

12) a) Calculate the advantage for P(A(R) = 1) = 0.9 and P(A(G(s)) = 1) = 0.2

b) Can G be considered as a good PRG?

13) What is the purpose of Support Vector Machines (SVMs)?

14) What can be done if you only have a technique to learn a linear classifier but the data is not linear separable?

15) What is contextual anomaly

16) Which sample has higher Entropy. (Slide 05 / 40)