B.TECH - Semester 8 crytography and networks security Question Paper 2008 (may)
Practice authentic previous year university questions for better exam preparation.
Sample Questions
- What is the difference between a block cipher and a stream cipher? Give one example of each.
- Encrypt the sentence cryptographic techniques' using Vignere cipher with key a 'cryptanalysis'.
- What parameters determine the actual algorithm of a Feistel cipher?
- What is Euler's totient function $(\varphi(n))$ ? Write all numbers which are relatively prime to 15.
- What is a message authentication code?
- What is the purpose of the state array?
- How SSL connection is different from SSL session?
- What is man in the middle attack of Diffie-Hellman key exchange algorithm?
- Write any four security requirements of Cryptographic Hash Functions.
- What are Enveloped data, signed data and clear-signed data in the context of S/MIME? Answer one full question from each module. Each question carries 20 marks.
- (a) How Monoalphabetic ciphers differ from Polyalphabetic ciphers? Explain with one example from each.
- (b) Draw diagrams showing encryption and decryption in Cipher Feedback (CFB) mode of DES.
- (c) Describe Mixcolumns operation of AES.
- (a) What are transposition ciphers. Illustrate with an example.
- (b) What are the different primitive operations in IDEA. Explain the encryption process of IDEA.
- (c) Explain the operation performed in S Box of DES.
- (a) Explain the different operations by which 128 bit hash value is generated from a message by MD5 algorithm.
- (b) Write RSA algorithm. Perform encryption and decryption using the RSA algorithm for $p-5 ; q=11 ; e=3 ; M=9$. OR
- (a) Explain how signing and verification is performed in Digital Signature algorithm.
- (b) Explain how a common key is established between communicating parties using Diffie-Hellman Algorith
- (a) What steps are involved in SSL Record Protocol transmission? 10
- (b) List the applications of IPSec. What are the benefits of IPSec. 10
- (a) What are the firewalls? What are different types of firewall? $\mathbf{1 0}$
- (b) Distinguish between transport mode and tunnel mode operation in IP security? ( $\mathbf{3} \boldsymbol{\times} \mathbf{2 0} \boldsymbol{=} \mathbf{6 0}$ Marks)