Information & Network Security Past Paper PDF (R-2023)

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A4 1C 2D 35 BB Paper / Subject Code: 82909 / Computer Science: Information & Network Security (R-2023) CD CD 4C 5F D2 16 35 DA BB D1 C2 CA 5F D2 5C BC A4 16 BD C2 3 B CD A 5F D2 8F 4 C (2 ½ Hours) [Total Marks: 75] 6 5 A D 1 2 F3 5C CD B CA C 65 8F A4 9F 35 D A1 C2 5C N.B. 1) All questions are compulsory. 9C D FB 5F 5C A4 DC 9F 1C 2) Figures to the right indicate marks. 16 C8 F3 C D CD FB CA 3) Illustrations, in-depth answers and diagrams will be appreciated. 5 9 5C 65 F 1C 8 BB C9 BD A1 4) Mixing of sub-questions is not allowed. F3 C D F5 C9 D2 5 BC 8F DC 16 9 1 3 5C C2 C B D FB CA 5F Q. 1 Attempt ANY FOUR from the following: (20M) 9 D2 BC 9F A4 1C 16 C8 (a) Define computer security. What are the objectives of computer security? BD 2 C B CD D CA C F5 C9 (b) What is an active attack in security? State various types of active attacks. D2 C 8F A4 35 B C9 BD 1 (c) Write a note on Steganography. 5C C2 B D CD 5F C9 D2 C 8F (d) Encrypt the following message using Rail Fence Algorithm with key size = 4. 9F A4 16 35 B BD D1 C C2 9C Plaintext = they are attacking from the north. B D CA F F5 2 5C BC 8F 5 A4 1C 2D (e) Explain Electronic Code Book(ECB) mode in cryptography. 6 C9 BD 1 5C F3 2B D CD CA C (f) Differentiate substitution and transposition techniques. C9.in 5C 5 8F 9F 4 2D 16 A BB D D1 F3 5C 9C D B A 4C Q. 2 Attempt ANY FOUR from the following: (20M) D2 5C BC 5 8F DC 9F 1C 16 A (a) Write a note on public key cryptosystem. C2 F3 5C 9C 2B CD CD B CA (b) Describe X.509 certificate format. 5 F A4 9F 1C 2D 16 35 8 BB BD C 9C (c) Assume Alice and Bob wish to communicate secretly. Compute the shared CD CD es A 4C F F5 D2 5 8F C 1C secret key using Diffie Hellman Key Exchange. 16 35 DA BB C9 BD C2 C [Prime number p = 7, generator g = 3, Alice’s private key = 2, Bob’s private CD CA 5F 5 C9 D2 5C F A4 F 16 key = 4] C8 BB C9 BD 1 F3 C2 CD CD A F5 (d) How does HMAC algorithm work? 9 D2 65 8F DC A4 C ot 35 BB 9 (e) Discuss the concept of a digital signature. Explain its types. 1 A1 C C2 C CD CD B 5F 5 9 D2 (f) Explain kerberos processing in detail. 8F DC 9F A4 1C 16 5 BB 5C C2 F3 9C CD D FB CA 2 BC 65 9F A4 1C Q. 3 Attempt ANY FOUR from the following: (20M) D 8 35 BD un A1 C 2 9C B CD CD (a) What is a firewall? State and explain various types of firewall. 4C 5F F5 2 8F DC 1C D (b) Explain the importance of web security. 16 35 A B C9 5C 2 B CD CD FB CA 4C 5F (c) What is S/MIME (Secure/Multipurpose Internet Mail Extensions)? Define its C9 D2 9F 16 35 A BB key features. BD D1 C2 9C CD CA 5F 2 (d) Describe IP security architecture. BC 8F A4 1C 2D 16 35 m BD (e) State and explain any 5 types of virus. 5C 2B CD CD CA 4C 5F 8F (f) Write a note on honeypots. F 2D 16 35 DA BB C9 BD 5C CA 4C 5F C9 D2 5C 8F F Q. 4 Attempt ANY FIVE from the following: (15M) 16 DA C9 BD C2 F3 5C CA (a) Define terms : C9 5C 5 8F A4 F 16 C9 i. Cryptanalysis BD D1 F3 5C CD A C9 ii. Brute Force Attack 65 BC 8F C F 35 C9 D 1 1 (b) What is message authentication code? 5C 2B CD FB CA 5F C9 (c) State any two common forms of malicious code. F 16 C8 BB C9 BD 1 (d) Using Caesar cipher with key size = 3, encrypt the message “hide the gold and CD CA 5 C9 D2 F F defend east wall” C8 BB C9 BD 1 C2 CD (e) What are the three properties of Hash function? 5 C9 D2 8F F A4 BB (f) Explain the life cycle of viruses. 9 1 5C C2 9C CD CD D2 9F 4 1C DA BB C2 ***************** 9C CD D2 C 4 1C 35 DA BB C2 CD F 2 40170 C 65 4 2D 35 DA BB 1 CA C F D2 C 65 A4 35 1 C2 D CA F C8FBDCA165F35CDA4C2D2BBCD1C9C9F5 5C 65 A4