Cyber Security (4353204) - Unit 1 & Unit 2 Question Bank

Government Polytechnic Palanpur

Information & Communication Technology

Cyber Security (4353204) - Unit 1 & Unit 2 Question Bank

Subject Name & Code: Cyber Security (4353204)
Semester: 5
Coverage: Unit 1 & Unit 2
Question Types: Short Answer & Long Answer

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Unit I: Introduction to Cyber Security & Cryptography

Important Questions from Unit 1

Question 1 [7 marks]

Explain various security attacks, mechanisms, and services associated with each layer of the OSI model.

Answer:

OSI Security Framework:

Key Security Services:

• Authentication: Verifying user identity
• Authorization: Controlling access permissions
• Non-repudiation: Preventing denial of actions
• Data integrity: Ensuring data accuracy

Mnemonic: "All People Seem To Need Data Protection"

Question 2 [3 marks]

Describe CIA triad with example.

Answer:

CIA Triad Components:

• Confidentiality: Only authorized users can access sensitive information
• Integrity: Data remains accurate and unaltered during transmission
• Availability: Systems remain operational and accessible to legitimate users

Mnemonic: "CIA Keeps Information Safe"

Question 3 [7 marks]

Explain MD5 hashing and Secure Hash Function (SHA) algorithms.

Answer:

Diagram:

Key Differences:

Answer:

Hash Function Comparison:

MD5 Algorithm Process:

1. Input Processing: Message is padded and divided into 512-bit blocks
2. Initialization: Sets up four 32-bit registers with fixed values
3. Compression: Processes message in 16-word blocks through four rounds of operations
4. Output: Produces 128-bit digest as final hash value

SHA Algorithm Features:

• Deterministic: Same input produces same hash
• Avalanche Effect: Small input change causes major hash change
• One-way Function: Cannot reverse hash to original data
• Collision Resistant: Difficult to find two inputs with same hash

Applications:

• Password storage and verification
• Digital signatures and certificates
• Data integrity verification

Mnemonic: "Hash Always Produces Same Output"

Question 4 [3 marks]

Explain Public key and Private Key cryptography.

Answer:

Public Key Cryptography (Asymmetric):

Key Characteristics:

• Public Key: Used for encryption and signature verification
• Private Key: Used for decryption and digital signing
• Security: Based on mathematical complexity (RSA, ECC algorithms)

Example: In RSA encryption, if Alice wants to send Bob a message:

1. Alice encrypts with Bob's public key
2. Only Bob can decrypt using his private key

Mnemonic: "Public Encrypts, Private Decrypts"

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Unit II: Account and Data Security

Important Questions from Unit 2

Question 5 [7 marks]

Explain working of packet filter and application proxy.

Answer:

Diagram:

Key Differences:

Mnemonic: "Packets Check Headers, Proxies Check Content"

Question 6 [3 marks]

What is authentication? Explain different methods of authentication.

Answer:

Authentication Definition: Process of verifying user identity before granting system access.

Authentication Methods:

• Single-Factor: Uses one authentication method
• Multi-Factor: Combines multiple methods
• Two-Factor (2FA): Uses exactly two factors

Mnemonic: "Password Biometric Token Authentication"

Question 7 [7 marks]

Explain different types of malicious software and their effect.

Answer:

Malware Classification:

Effects on Systems:

• Performance: Slow system response
• Data: Loss, corruption, or theft
• Privacy: Unauthorized monitoring
• Financial: Direct monetary loss

Prevention Methods:

• Regular antivirus updates
• Safe browsing practices
• Email attachment caution
• System security patches

Mnemonic: "Viruses Worms Trojans Really Steal All Resources"

Question 8 [3 marks]

What is firewall? List out types of firewalls.

Answer:

Firewall Definition: Network security device that monitors and controls incoming/outgoing traffic based on security rules.

Types of Firewalls:

• Hardware Firewall: Dedicated network appliance
• Software Firewall: Installed on individual computers
• Cloud Firewall: Delivered as a service (FWaaS)

Mnemonic: "Firewalls Protect Networks Always"

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Study Tips for Unit 1 & Unit 2

Unit 1 Focus Areas

1. Security Fundamentals - OSI model security layers
2. CIA Triad - Core principles of information security
3. Cryptography Basics - Hash functions and encryption types

Unit 2 Focus Areas

1. Network Security - Firewalls, packet filtering, proxies
2. Authentication Systems - Methods and multi-factor authentication
3. Malware Analysis - Types, effects, and prevention strategies

Exam Preparation Tips

• Practice drawing network diagrams and security frameworks
• Memorize comparison tables for different security technologies
• Understand real-world applications of theoretical concepts
• Focus on the working principles behind security mechanisms
• Review mnemonics for better concept recall

Key Topics Coverage

• Unit 1: Introduction to Cyber Security, Security Models, Cryptographic Foundations
• Unit 2: Network Security, Authentication Mechanisms, Threat Analysis

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Note: These questions cover fundamental concepts from Unit 1 and Unit 2 that are commonly asked in examinations. Practice these thoroughly for better understanding of cyber security principles.