M.Sc. DEGREE EXAMINATION, NOVEMBER 2017
Third Semester
Computer Science
CRYPTOGRAPHY AND NETWORK SECURITY
(CBCS 2014 onwards)
Time 3 Hours Maximum 75 Marks
Part A (10 x 2 20)
Answer all questions.
1. Define the term vulnerability.
2. What are the five ingredients of symmetric cipher?
3. How block cipher is different from stream cipher?
4. Give the importance for Diffusion.
5. Differentiate conventional encryption and public-key
encryption.
6. What is an elliptic curve?
7. List two disputes that can arise in the context of message
authentication.
8. Write down any two advantages of Digital signature.
9. What is PGP?
10. What are the benefits of IPSec?
Sub. Code
4MCE3C1
AFF-4961
2
wk14
Part B x 5 25)
Answer all questions.
11. Briefly explain about the network security model
with neat diagram.
Or
Explain about Transposition cipher with an
example.
12. Why is it important to study the Feistel cipher?
Explain.
Or
Give the importance for state array.
13. What are the elements of a public-key
cryptosystem? Explain.
Or
List four general categories of schemes for
distribution of public-keys.
14. Give the importance for Hash function.
Or
Discuss on EIGamal Digital Signature scheme in
briefly.
15. What is handshake protocol? Explain.
Or
Differentiate transport and tunnel mode
functionality.
AFF-4961
3
wk14
Part C x 10 30)
Answer any three questions.
16. Explain about the various kinds of security attacks with
an example.
17. Describe about the Overall structure of AES with neat
sketch.
18. Explain in detail about RSA algorithm with an example.
19. Give a detailed note on authentication requirements.
20. Discuss on Encapsulating Security Payload with neat
diagram.
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