Define authentication system. Discuss about challenge response system.[5]
Cryptographic Hash Functions and Digital Signatures
1.
Describe the properties of hash functions. Discuss how hash value is generated using SHA-1 algorithm.[10]
2.
Describe the working mechanism of digital signature algorithm.[5]
Introduction and Classical Ciphers
1.
Describe the Feistel Cipher structure. Given the key {2B, 7E, 15, 16, 28, AE, D2, A6, AB, F7, 97, 66, 01, 02, 03, 04}, compute the first 4 byte of next key after first iteration, using the following S-Box in AES.
Given the key "HELLOWORLD", encrypt the plaintext "TURINGTEST" using Play fair cipher.[5]
3.
Decrypt the ciphertext 'HI' using Hill Cipher where the key is.
Ciphertext: HI, Key: [5433]
[5]
Malicious Logic
1.
Describe any three types of malicious logic.[5]
Network Security and Public Key Infrastructure
1.
List and explain the types of firewall.[5]
2.
What is digital certificate? Discuss the certificate life cycle.[5]
Symmetric Ciphers
1.
Illustrate the man in middle attack in Diffie-Hellman key exchange protocol. Assume the prime number be 19 and 10 as its primitive root. Select 5 as private key and 4 as random integer. Find the cipher text of M = 2 using Elgamal crypto system.[10]
2.
Explain any two modes of block cipher encryption.[5]
3.
State Fermat's theorem with example. What is the implication of discrete logarithm?[5]