Cryptography & Network Security Unit 1 – Security Foundations, Classical Encryption and Modern Block Ciphers: important questions for AKTU
Unit 1 (Security Foundations, Classical Encryption and Modern Block Ciphers) questions that AKTU repeats most often. This unit carries about 29 marks per paper. Start with the repeated questions, then the most asked topics.
Most repeated Unit 1 questions
- Discuss Shannon’s theory of confusion and diffusion. Explain. (7 marks, 2026, Shannon Confusion and Diffusion) – also asked in 2019, 2021, 2023
- Discuss the working of DES in detail with suitable diagram. (10 marks, 2024, Data Encryption Standard (DES)) – also asked in 2018, 2019
- What is the Shannon’s theory of confusion and diffusion in terms of information security? (10 marks, 2019, Shannon Confusion and Diffusion) – also asked in 2021, 2023, 2026
Most important Unit 1 topic
- Classical Encryption Techniques (Unit 1: Security Foundations, Classical Encryption and Modern Block Ciphers) – asked 10 times in 2020, 2021, 2022, 2023, 2025, 2026
Most asked Unit 1 topics
- Classical Encryption Techniques – asked 10 times
- Data Encryption Standard (DES) – asked 8 times
- Block Cipher Modes of Operation – asked 6 times
More Unit 1 previous year questions
- Compare steganography and Cryptography. (2 marks, 2026, Steganography)
- Define cryptography and state any two security services. (2 marks, 2026, Security Services)
- What is the difference between stream cipher and block cipher? (2 marks, 2026, Stream and Block Ciphers)
- Explain substitution and transposition ciphers with suitable examples. (7 marks, 2026, Classical Encryption Techniques)
- Compare and contrast Output Feedback (OFB) and Counter mode of Block cipher. (7 marks, 2026, Block Cipher Modes of Operation)
Unit 1 syllabus topics
- Security Attacks
- Security Services
- Security Mechanisms
- Classical Encryption Techniques
- Cryptanalysis
- Steganography
- Stream and Block Ciphers
- Block Cipher Principles
- Shannon Confusion and Diffusion
- Feistel Structure
- Data Encryption Standard (DES)
- Differential Cryptanalysis