1. Suppose H(m) is a collision-resistant hash function that maps a message of arbitrary bit length into an n-bit hash value. Is it true that, for all messages x, x' with x o x', we have H(x) o H(x')? Explain your answer.
2. Perform encryption and decryption using the RSA algorithm (Figure 3.10) for the following: p = 11; q = 13; e = 11; M= 7. Make sure you show both the resulting ciphertext and plaintext equations for encryption and decryption, respectively. Show your work! )
3. Consider a Diffie-Hellman scheme with a common prime q = 11 and a primitive root a = 2.
a. If user A has public key YA = 9, what is A's private key XA? Show your work!
b. If user B has public key YB = 3, what is the shared secret key K? Show your work!
4. Consider a one-way authentication technique based on asymmetric encryption:
A 4 B: /DA
B 4 A: E(P U., R2)
A 4 B: R2
a. Explain the protocol.
b. What type of attack is this protocol susceptible to? (5 points)
5. Is it possible in SSL for the receiver to reorder SSL record blocks that arrive out of order? If so, explain how it can be done. If not, why not? (2 points)