Cryptography & System Security - May 2016

Computer Engineering (Semester 7)

TOTAL MARKS: 80
TOTAL TIME: 3 HOURS (1) Question 1 is compulsory.
(2) Attempt any three from the remaining questions.
(3) Assume data if required.
(4) Figures to the right indicate full marks. 1(a) Explain software flaws with examples.(5 marks) 1(b) List with examples the different mechanisms to achieve security.(5 marks) 1(c) Explain with examples,keyed and keyless transposition chipers.(5 marks) 1(d) Elaborate the steps of key generation using RSA algorithm.(5 marks) 2(a) A and B decide to use Diffie Hellman algorithm to share a key. They chose p=23 and g=5 as the public parameters. Their secret keys are 6 and 15 respectively. Compute the secret key that they share.(10 marks) 2(b) Explain working of DES.(10 marks) 3(a) What is access control? How does the Bell La Padula model achieve access control.(10 marks) 3(b) What is a digital signature. Explain any digital signature algorithm in detail.(10 marks) 4(a) Compare packet sniffing and packet spoofing. Explain session hijacking attack.(10 marks) 4(b) Explain working of Kerberos.(10 marks) 5(a) What is firewall? What are the firewall design principle?(5 marks) 5(b) What are the various ways for memory and address protection?(5 marks) 5(c) Explain the significance of an Intrusion Detection System for securing a network. Compare signature based and anomaly based IDS.(10 marks)

Write in brief about (any four):

6(i) Email Security(5 marks) 6(ii) SSL handshake protocol(5 marks) 6(iii) IPSec protocols for security(5 marks) 6(iv) Denial of service attacks(5 marks) 6(v) IDEA(5 marks)