Information Security — CACS459 (8th Sem)

ce ll Tribhuvan University KOs y Faculty of Humanities & Social Sciences EDR olin tEN OFFICE OF THE DEAN x Vv 2025 Bachelor in Computer Applications Course Title: Information Security Full Marks: 60 Code No: CACS 459 Pass Marks: 24 Semester: VII Time: 3 hours Candidates are required to answer the questions in their own words as far as possible. Group B Attempt any SIX questions. [6x5 = 30] 2. What is security? Explain different type of passive attack with example: [1+4] _3. What is confusion and diffusion? Decrypt the cipher text CDFNFTDTSBEQ with the key | FOHSS using Playfair cipher, = Se (23a. = |S BeinKey Sched fAESalgrihm, gp i a 7. What is dina 'sipnatu re? List and explain the pHESe” . compu iter Virus? (243) Ee 3. What is audit trail? Why is it important in security auditing? [2+3] | Group C Attempt any TWO questions. [2x10 = 20] : 3 9. What do you mean by "Feistel Structure for Block Ciphers"? Explain with block diagram. How te - as _ can a number can be tested for primality testing using Miller-Rabin algorithm? Explain with Pa eliblecxample, Sts ___ 19. Explain the properties of hash functions. Discuss how hash value is generated using SHA-]