Visvesvaraya Technological University (VTU) 2007 B.E Computer Science Eighth Semester Engineering , / 2006-Cryptography and Network Security - Question Paper

Eighth Semester B.E. Degree Engineering Examination, May/Jun 2006
CSE/ISE
Cryptography and Network Security
Time: three hrs Max.Marks:100
Note: ans any 5 full ques.
1 a. What is meant by info security? explain about Attacks, Services and
Mechanisms of info security? (10 marks)
b. With a suitable example discuss the Playfair and Hill cipher (10 marks)

2 a. With schematic diagrams discuss the S-DES Encryption and Decryption techniques
in detail. (10 marks)
b. How subkeys and S-boxes are generated in blow Fish algorithm? explain
about Blow-Fish Encryption technique. (10 marks)

3 a. Distinguish ranging from Link encryption and End to End encryption giving
Characteristics of both methods. (10 marks)
b. With a suitable example define the RSA algorithm. explain about security of RSA. (10 marks)

4 a. What is multiplicative inverse? Write an algorithm to implement it. (10 marks)
b. Compare and contrast Direct Digital Signature and Arbitrated Digital Signature. (10marks)

5 a. What is a Kerberos? explain about motivatiob and requirements for the Kerbose
Approach. (10 marks)
b. What is meant by S/MIME? List and discuss the different functions given by
S/MIME. (10 marks)

6 a. Why do we need IP level security? List and discuss the different services of IP
Security. (10 marks)
b. With a diagram discuss the structure of IP secutity authentication Header.
(10 marks)

7 a. provide the summary of web security threats, consequences and counter measures.
(10 marks)
b. provide the basic architecture of SSI Protocol stack, discuss the SSL alert protocol
operations. (10 marks)

8 a. Who is an Intruder? How many classes of ?Intruder exist? List the different techniques
For learning password.
b. What is meant by Firewall? Mention different kinds of Firewall and explain.
(10 marks)

Earning:   Approval pending.