Cryptography & Network Security Unit 3 – Message Authentication, Hash Functions and Digital Signatures: AKTU previous year questions
12 AKTU questions from Unit 3 (Message Authentication, Hash Functions and Digital Signatures) asked in 2025–2026, tagged by marks, year and topic. In short: about 26 marks of every paper come from this unit; the most asked topic is Secure Hash Algorithm (SHA) (10 times); 4 questions came back in a later year. The latest ones are listed below; on the page you can filter them by 2-mark or long questions, topic and repeats.
Unit 3 previous year questions
- Explain requirement of Hashing. (2 marks, 2026, Hash Functions)
- What is the purpose of a digital signature? (2 marks, 2026, Digital Signatures)
- State and proof digital signature standard (DSS). (7 marks, 2026, Proof of Digital Signature Algorithm)
- Explain authentication requirements and hash functions. Discuss birthday attack. (7 marks, 2026, Hash Functions)
- Explain Hash Function? Discuss SHA- 512 with all required steps, round function & block diagram. (7 marks, 2026, Secure Hash Algorithm (SHA))
- Describe Secure Hash Algorithm (SHA) and its security features. (7 marks, 2026, Secure Hash Algorithm (SHA))
- Discuss the Message Authentication Codes. Also give the use of Authentication requirements in MAC. (7 marks, 2026, Message Authentication Codes)
- Explain ElGamal Digital Signature technique and Digital Signature Standard (DSS). (7 marks, 2026, ElGamal Digital Signature Techniques)
- Explain Birthday attack (2 marks, 2025, Birthday Attacks)
- Illustrate the idea of Digital Signature for authentication. Discuss signing & verifying process of Digital Signature Algorithm (DSA) in detail with suitable steps. (10 marks, 2025, Digital Signatures)
- Explain the concept of MAC. Discuss the working of MAC with suitable block diagram. (10 marks, 2025, Message Authentication Codes)
- Discuss SHA- 512 with all required steps, round function & block diagram. (10 marks, 2025, Secure Hash Algorithm (SHA))
Most asked Unit 3 topics
- Secure Hash Algorithm (SHA) – asked 10 times
- Digital Signatures – asked 8 times
- Message Authentication Codes – asked 6 times
Unit 3 question pattern
- 2-mark questions: 3 asked in 2025–2026
- 7-mark questions: 6 asked in 2025–2026
- 10-mark questions: 3 asked in 2025–2026
- About 26 marks from Unit 3 in every paper
- 4 questions were asked again in a later year
Unit 3 questions year by year
- 2026: 8 Unit 3 questions asked (46 marks across that year's papers)
- 2025: 4 Unit 3 questions asked (32 marks across that year's papers)