a) Explain transposition cipher and polyalphabetic cipher. (Unit 1)

b) Write differences between symmetric key ciphers and asymmetric key ciphers. (Unit 1)

a) Explain the encryption process in AES algorithm. (Unit 2)

b) Describe ECB mode of block ciphers with a neat diagram. (Unit 2)

a) Explain Davies-Meyer construction of hash function. (Unit 3)

b) Illustrate one-way trapdoor functions with an example. (Unit 3)

a) Describe how encryption and decryption is performed in Elliptic Curve cryptography. (Unit 4)

b) Explain the steps of man in the middle attack. (Unit 3)

a) Describe Euler's theorem for identifying prime numbers with an example of your own. (Unit 5)

b) Illustrate discrete logarithmic problem and how it is useful in cryptography? (Unit 4)

a) Write differences between AES and DES algorithms. (Unit 2)

b) Explain how authentication can be done using digital signatures? (Unit 5)

a) Explain the disadvantages of RSA algorithm. (Unit 5)

b) Perform encryption and decryption using RSA algorithm for $p=5$ $q=11$, $e=3$ and $M=9$. (Unit 5)

Write short notes on:

i) DES encryption (Unit 2)

ii) Play Fair Cipher (Unit 1)

iii) Diffie-Hellman Key Exchange Algorithm (Unit 4)