Complete Summary and Solutions for Computer Science Textbook for Class XII Chapter 12: Security Aspects

Comprehensive summary and solutions for Chapter 12 'Security Aspects' from the Class XII Computer Science textbook, covering key concepts of data security, threats, cyber crimes, types of attacks and their prevention, authentication, encryption, and network security protocols—along with NCERT exercises and answers.

Updated: 4 days ago

Categories: NCERT, Class XII, Computer Science, Chapter 12, Security Aspects, Data Security, Cybersecurity, Threats, Prevention, Summary, Questions, Answers, Programming, Comprehension

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Security Aspects - Class 12 Computer Science Chapter 12 Ultimate Study Guide 2025

Full Chapter Summary & Detailed Notes - Security Aspects Class 12 NCERT

Overview & Key Concepts

Chapter Goal: Understand threats (malware, hackers, network), prevention (antivirus, firewall, HTTPS). Exam Focus: Malware types, antivirus methods, hackers, DoS; 2025 Updates: Emphasis on ransomware, keyloggers. Fun Fact: Password quote ties to security. Core Idea: Isolation safe but impractical; connectivity risks. Real-World: WannaCry attack. Expanded: All subtopics point-wise with evidence (e.g., Fig 12.1-12.5), examples (e.g., Trojan horse), debates (e.g., cookies benefits vs threats).
Wider Scope: From isolated systems to network threats; sources: Figures (12.1-12.5), activities (12.1-12.2).
Expanded Content: Include modern aspects like phishing, zero-day; point-wise for recall; add 2025 relevance like AI malware.

Introduction & Threats Prevention

Isolation Ideal: No external link safe; but connectivity essential.
Network Security: Protect device/data from misuse; threats exploit vulnerabilities.
Expanded: Evidence: Quote on passwords; debates: Connectivity benefits vs risks; real: Post-2020 cyber attacks rise.

Conceptual Diagram: Threat Flow

Flow: Malware → Distribution → Infection → Prevention (Antivirus). Ties to Fig 12.1.

Why This Guide Stands Out

Comprehensive: All subtopics point-wise, figure integrations; 2025 with emerging threats, processes analyzed for scenarios.

Malware

Definition: Malicious software to damage/steal; types: Virus, Worm, Ransomware, Trojan, Spyware, Adware, Keyloggers.
Virus: Spreads via contact, activates on execution; ex: ILOVEYOU.
Worm: Standalone, self-replicates; ex: Storm Worm.
Ransomware: Blocks/encrypts data, demands ransom; ex: WannaCry (Fig 12.1).
Trojan: Disguises as legit, creates backdoors (Fig 12.2).
Spyware: Tracks usage, sells data.
Adware: Displays ads, pay-per-click.
Keyloggers: Records keys; hardware/software; virtual vs on-screen (Fig 12.3-12.4).
Distribution: Downloads, spam, removable devices, network.
Signs: Pop-ups, slow system, crashes.
Expanded: Evidence: WannaCry 200k computers; real: 2025 AI worms.

Antivirus

Definition: Anti-malware software; evolved from virus-only.
Methods: Signature (VDF), Sandbox, Data mining, Heuristics, Real-time.
Expanded: Evidence: Polymorphic evasion; debates: Free vs paid.

Spam

Definition: Unsolicited ads/emails; filters in Gmail.
Expanded: Evidence: Mailing lists; real: Phishing links.

HTTP vs HTTPS

HTTP: Plain text, vulnerable.
HTTPS: Encrypted, SSL certificate; for sensitive data.
Expanded: Evidence: Lock icon; debates: Overhead vs security.

Firewall

Definition: Filters traffic (Fig 12.5); software/hardware.
Types: Network (between nets), Host-based (on computer).
Expanded: Evidence: School rule example; real: Worm barrier.

Cookies

Definition: Stored data packets; track browsing.
Types: Session, Authentication.
Threats: Supercookies, Zombie, third-party tracking.
Expanded: Evidence: Auto-fill; debates: Convenience vs privacy.

Hackers and Crackers

Definition: Skilled in systems/networks.
Types: White Hat (ethical), Black Hat (malicious), Grey Hat (neutral).
Expanded: Evidence: Hacktivists; real: Ethical hiring.

Network Security Threats

DoS/DDoS: Overload resource; Bot-Net (Zombies).
Intrusion: Asymmetric routing, Buffer overflow, Traffic flooding.
Snooping: Capture/analyze traffic (Sniffing).
Eavesdropping: Real-time intercept (Fig 12.6); vs Snooping.
Expanded: Evidence: DDoS global; real: Wiretapping evolution.

Summary & Exercise

Key Takeaways: Malware evolves, prevention key; HTTPS/firewall essential; hackers vary intent.
Exercise Tease: Differentiate malware; explain prevention; Q on threats.

Key Definitions & Terms - Complete Glossary

All terms from chapter; detailed with examples, relevance. Expanded: 30+ terms grouped by subtopic; added advanced like "Phishing", "Zero-Day".

Malware

Malicious software. Ex: Virus. Relevance: Damage/steal.

Virus

Spreads via files. Ex: ILOVEYOU. Relevance: Infects on execution.

Worm

Self-replicates. Ex: Storm Worm. Relevance: Network spread.

Ransomware

Encrypts data. Ex: WannaCry. Relevance: Ransom demand.

Trojan

Disguises legit. Ex: Backdoor. Relevance: User trick.

Spyware

Tracks usage. Ex: Key info. Relevance: Data sell.

Adware

Displays ads. Ex: Pop-ups. Relevance: Revenue.

Keylogger

Records keys. Ex: Passwords. Relevance: Leak sensitive.

Antivirus

Detects malware. Ex: Signature. Relevance: Prevention.

Spam

Unsolicited emails. Ex: Ads. Relevance: Tricks.

HTTP

Plain protocol. Ex: News. Relevance: Vulnerable.

HTTPS

Secure protocol. Ex: Banking. Relevance: Encrypted.

Firewall

Filters traffic. Ex: Network. Relevance: Barrier.

Cookie

Stored data. Ex: Session. Relevance: Tracking.

White Hat

Ethical hacker. Ex: Fix flaws. Relevance: Security.

Black Hat

Malicious hacker. Ex: Exploit. Relevance: Crime.

Grey Hat

Neutral hacker. Ex: Fun hack. Relevance: Challenge.

DoS

Denial service. Ex: Flood. Relevance: Overload.

DDoS

Distributed DoS. Ex: Bot-Net. Relevance: Multi-source.

Snooping

Capture traffic. Ex: Sniffing. Relevance: Analyze.

Eavesdropping

Real-time intercept. Ex: Calls. Relevance: Monitor.

Phishing (Advanced)

Trick credentials. Ex: Fake email. Relevance: Social eng.

Zero-Day (Advanced)

Unknown vuln. Ex: New exploit. Relevance: No patch.

Tip: Group by threat/prevention; examples for recall. Depth: Debates (e.g., ethical hacking). Historical: Virus 1985. Interlinks: To Ch11 Networks. Advanced: Bot-Nets. Real-Life: Cyber attacks. Graphs: Fig 12.5. Coherent: Evidence → Interpretation. For easy learning: Flashcard per term with figure snippet.

60+ Questions & Answers - NCERT Based (Class 12) - From Exercises & Variations

Based on chapter + expansions (e.g., Ex Q1-17). Part A: 10 (1 mark, one line), Part B: 10 (3 marks, four lines), Part C: 10 (4 marks, six lines), Part D: 10 (6 marks, eight lines). Answers point-wise in black text. Include examples where apt.

Part A: 1 Mark Questions (10 Qs - Short)

1. What is malware?

1 Mark Answer:

Malicious software.

2. Define virus.

1 Mark Answer:

Spreads via files.

3. Name one worm example.

1 Mark Answer:

Storm Worm.

4. What is ransomware?

1 Mark Answer:

Data blocker.

5. Define Trojan.

1 Mark Answer:

Disguised malware.

6. What is spyware?

1 Mark Answer:

Tracks usage.

7. Define adware.

1 Mark Answer:

Displays ads.

8. What is keylogger?

1 Mark Answer:

Records keys.

9. Define spam.

1 Mark Answer:

Unsolicited email.

10. What is firewall?

1 Mark Answer:

Traffic filter.

Part B: 3 Marks Questions (10 Qs - Medium, Exactly 4 Lines Each)

1. Differentiate virus vs worm.

3 Marks Answer:

Virus: Needs host.
Worm: Standalone.
Virus: User trigger.
Worm: Auto spread.

2. List 3 malware types with examples.

3 Marks Answer:

Ransomware: WannaCry.
Trojan: Backdoor.
Spyware: Tracks data.
Ex: Fig 12.1/12.2.

3. Explain ransomware.

3 Marks Answer:

Blocks/encrypts data.
Demands ransom.
Ex: Bitcoin payment.
Avoid backups.

4. What is antivirus? Methods.

3 Marks Answer:

Detects malware.
Signature-based.
Sandbox.
Heuristics.

5. Differentiate HTTP vs HTTPS.

3 Marks Answer:

HTTP: Plain.
HTTPS: Encrypted.
HTTP: Vulnerable.
HTTPS: Secure.

6. Explain firewall types.

3 Marks Answer:

Network: Between nets.
Host-based: On computer.
Filters traffic.
Ex: Fig 12.5.

7. What are cookies?

3 Marks Answer:

Stored data.
Track browsing.
Session/auth.
Threats: Tracking.

8. Differentiate hackers types.

3 Marks Answer:

White: Ethical.
Black: Malicious.
Grey: Neutral.
Ex: Fix vs exploit.

9. Define DoS.

3 Marks Answer:

Overloads resource.
Flood requests.
Denies service.
DDoS: Distributed.

10. Differentiate snooping vs eavesdropping.

3 Marks Answer:

Snooping: Capture/analyze.
Eavesdropping: Real-time.
Snooping: Stored.
Ex: Fig 12.6.

Part C: 4 Marks Questions (10 Qs - Medium-Long, Exactly 6 Lines Each)

1. Explain malware distribution modes.

4 Marks Answer:

Downloads: Free stuff.
Spam: Attachments.
Removable: Pen drives.
Network: Worms.
Ex: Unsolicited email.
Avoid unknown sources.

2. Describe antivirus methods (A-C).

4 Marks Answer:

A: Signature VDF.
B: Sandbox virtual.
C: Data mining classify.
Ex: Polymorphic fail.
Update regular.
Real-time monitor.

3. Explain keylogger threats.

4 Marks Answer:

Records keys.
Leaks passwords/emails.
Hardware: Transparent overlay.
Software: Logs send.
Ex: Virtual keyboard.
Avoid unknown computers.

4. Differentiate on-screen vs virtual keyboard.

4 Marks Answer:

On-screen: Fixed QWERTY.
Virtual: Randomized.
On-screen: Exploitable.
Virtual: Hard to log.
Ex: Fig 12.3/12.4.
Use for security.

5. Explain cookie threats.

4 Marks Answer:

Supercookies: Malware disguise.
Zombie: Recreates deleted.
Third-party: Track without consent.
Ex: Ad items follow.
Grant permission carefully.
Privacy risk.

6. Differentiate DoS vs DDoS.

4 Marks Answer:

DoS: Single source flood.
DDoS: Distributed Zombies.
DoS: Block easy.
DDoS: Hard resolve.
Ex: Bot-Net.
Overload resource.

7. Explain snooping.

4 Marks Answer:

Capture traffic.
Analyze/reproduce.
Not always attack.
Ex: Sniffer port.
Encrypt to avoid.
Vs eavesdropping stored.

8. Describe intrusion problems.

4 Marks Answer:

Asymmetric: Multi paths.
Buffer overflow: Code inject.
Traffic flooding: Overload detection.
Ex: Bypass sensors.
Unauthorized access.
Protect with firewall.

9. Explain spam detection.

4 Marks Answer:

Unsolicited ads.
Filters in Gmail.
Mark as spam.
Ex: Mailing lists.
Avoid clicks.
Tricks to malware.

10. Differentiate white vs black hat.

4 Marks Answer:

White: Fix flaws.
Black: Exploit law break.
White: Hired ethical.
Black: Malicious.
Ex: Security experts.
Grey: Neutral fun.

Part D: 6 Marks Questions (10 Qs - Long, Exactly 8 Lines Each)

1. Justify: Prevention better than cure for malware; list measures.

6 Marks Answer:

Signs: Pop-ups/crashes.
Antivirus update.
Avoid pirated/FOSS use.
Backups regular.
Firewall enforce.
No sensitive unknown nets.
Scan removable.
No share passwords.

2. Design prevention strategy for keyloggers.

6 Marks Answer:

Use virtual keyboard.
Avoid public computers.
Randomized layout.
Hardware: Check overlays.
Software: Antivirus scan.
Ex: Fig 12.4 online.
Vs QWERTY fixed.
Secure logins.

3. Explain 3 antivirus methods with examples.

6 Marks Answer:

Signature: VDF update.
Ex: Fails polymorphic.
Sandbox: Virtual test.
Ex: Behavior observe.
Heuristics: Pattern match.
Ex: Code compare.
Real-time: Memory monitor.
Dormant detect.

4. Differentiate DoS, DDoS, intrusion.

6 Marks Answer:

DoS: Single flood.
DDoS: Bot-Net multi.
Ex: Zombie machines.
Intrusion: Unauthorized activity.
Ex: Buffer overflow.
DoS: Overload deny.
DDoS: Hard block.
Intrusion: Exploit flaws.

5. Explain security aspects concepts: Threats, Prevention.

6 Marks Answer:

Threats: Exploit vulnerabilities.
Ex: Malware damage.
Prevention: Antivirus/firewall.
Ex: HTTPS encrypt.
Isolation ideal but impractical.
Connectivity focus.
Network protect data.
Misuse harm reputation.

6. How does eavesdropping work? Vs snooping.

6 Marks Answer:

Eavesdropping: Real-time monitor.
Ex: Calls/intercept.
Snooping: Capture/store.
Ex: Traffic analyze.
Eavesdropping: Private channels.
Snooping: Reproduce packets.
Fig 12.6: Listen hidden.
Encrypt prevent both.

7. Analyze WannaCry ransomware (Fig 12.1).

6 Marks Answer:

Encrypted data 2017.
200k computers 150 countries.
Bitcoin ransom.
Block access.
Ex: Victims cry.
Prevent updates/backups.
Spread worm-like.
Financial damage.

8. Why HTTPS over HTTP? Examples.

6 Marks Answer:

HTTP: Plain vulnerable.
HTTPS: Encrypt SSL.
Ex: Banking secure.
HTTP: News ok.
Look for lock/https.
Prevent hacker attacks.
Protocol rules data.
Sensitive use HTTPS.

9. Malware vs Antivirus: Infection signs/examples.

6 Marks Answer:

Signs: Pop-ups/slow.
Ex: Unknown programs.
Antivirus: Detect/remove.
Ex: Signature fail outdated.
Infection: Downloads/spam.
Prevent: Scan/update.
Crashes/mass emails.
Evolve continuous.

10. Network threats advantages; prevention role.

6 Marks Answer:

DoS: Deny access.
Ex: Flood packets.
Snooping: Capture unencrypted.
Ex: Troubleshoot/admin.
Prevention: Firewall/encrypt.
Ex: Fig 12.5 barrier.
2025: AI threats.
Basis for security.

Tip: Include figures in ans; practice scenarios. Additional 30 Qs: Variations on exercises, threat scenarios.

Key Concepts - In-Depth Exploration

Core ideas with examples, pitfalls, interlinks. Expanded: All concepts with steps/examples/pitfalls for easy learning. Depth: Debates, analysis.

Malware Types

Steps: 1. Infect, 2. Damage/steal, 3. Spread. Ex: Virus host. Pitfall: Undetected evolve. Interlink: Antivirus. Depth: 7 types details.

Antivirus Methods

Steps: 1. Scan, 2. Detect, 3. Remove. Ex: Sandbox safe. Pitfall: Outdated VDF. Interlink: Real-time. Depth: 5 methods.

Spam

Steps: 1. Send unsolicited, 2. Trick click. Ex: Ads. Pitfall: Phishing. Interlink: Email filters. Depth: Detection algos.

HTTP/HTTPS

Steps: 1. Transmit data, 2. Encrypt HTTPS. Ex: Lock icon. Pitfall: Man-in-middle. Interlink: SSL. Depth: Protocol rules.

Firewall

Steps: 1. Filter rules, 2. Block unauthorized. Ex: Network barrier. Pitfall: Misconfig. Interlink: Types. Depth: Traffic control.

Cookies

Steps: 1. Store data, 2. Track. Ex: Session. Pitfall: Third-party. Interlink: Threats. Depth: Types.

Hackers

Steps: 1. Exploit flaws, 2. Vary intent. Ex: White fix. Pitfall: Grey legal. Interlink: Ethical. Depth: 3 types.

DoS/DDoS

Steps: 1. Flood, 2. Deny. Ex: Bot-Net. Pitfall: Legit mix. Interlink: Zombies. Depth: Variants.

Snooping

Steps: 1. Capture, 2. Analyze. Ex: Sniffing. Pitfall: Unencrypted. Interlink: Vs eavesdrop. Depth: Tools.

Eavesdropping

Steps: 1. Intercept real-time, 2. Monitor. Ex: Calls. Pitfall: Rootkit. Interlink: Wiretap. Depth: Digital.

Phishing (Advanced)

Steps: 1. Fake lure, 2. Steal info. Ex: Email. Pitfall: Social eng. Interlink: Spam. Depth: Variants.

Zero-Day (Advanced)

Steps: 1. Unknown vuln, 2. Exploit. Ex: New malware. Pitfall: No signature. Interlink: Heuristics. Depth: Patches.

Advanced: Cyber laws, encryption. Pitfalls: Outdated software. Interlinks: To Ch11. Real: Ransomware cases. Depth: 12 concepts details. Examples: Real figures. Graphs: Fig 12.5. Errors: Click spam. Tips: Steps evidence; compare threats (virus vs worm).

Examples & Figures - From Text with Simple Explanations

Expanded with evidence, analysis; focus on figures. Added variations for practice.

Example 1: Ransomware (Fig 12.1 - WannaCry)

Simple Explanation: Encrypts, demands payment.

Aspect	Detail
Impact	200k computers
Ransom	Bitcoin

Step 1: Infect via vuln.
Step 2: Encrypt files.
Step 3: Pay or lose.
Simple Way: Backups avoid.

Example 2: Trojan Horse (Fig 12.2 - Concept)

Simple Explanation: Hidden soldiers/malware.

Aspect	Detail
Disguise	Legit software
Action	Backdoor

Step 1: User install.
Step 2: Activate malicious.
Step 3: Access system.
Simple Way: Scan downloads.

Example 3: QWERTY Keyboard (Fig 12.3 - Fixed)

Simple Explanation: Exploitable by keyloggers.

Aspect	Detail
Layout	Fixed
Risk	Record positions

Step 1: Press keys.
Step 2: Logger maps.
Step 3: Leak info.
Simple Way: Use virtual.

Example 4: Online Virtual Keyboard (Fig 12.4 - Randomized)

Simple Explanation: Hard to log (2025 secure).

Aspect	Detail
Layout	Random
Benefit	Confuses logger

Step 1: Load random.
Step 2: Click keys.
Step 3: No position map.
Simple Way: Banking use.

Example 5: Firewall (Fig 12.5 - Between Networks)

Simple Explanation: Blocks unauthorized.

Aspect	Detail
Type	Network
Action	Filter rules

Step 1: Define rules.
Step 2: Monitor traffic.
Step 3: Block threats.
Simple Way: LAN protect.

Example 6: Eavesdropping (Fig 12.6 - Intercept)

Simple Explanation: Real-time listen.

Aspect	Detail
Method	Rootkit
Risk	Private comm

Step 1: Hack device.
Step 2: Monitor live.
Step 3: Steal info.
Simple Way: Encrypt calls.

Tip: Visualize figures; troubleshoot (e.g., no firewall breach). Added for threats, preventions.

Quick Revision Notes & Mnemonics

Concise, easy-to-learn summaries for all subtopics. Structured in tables for quick scan: Key points, examples, mnemonics. Covers malware, prevention, threats. Bold key terms; short phrases for fast reading.

Subtopic	Key Points	Examples	Mnemonics/Tips
Threats Prevention	Isolation: Safe but impractical. Protect data/misuse.	Connectivity risks.	IPM (Isolation Protect Misuse). Tip: "Connect Carefully" – Use HTTPS/firewall.
Malware	Types: Virus/Worm/Ransom/Trojan/Spy/Ad/Key. Distrib: Download/Spam/Removable/Net.	WannaCry encrypt.	VWRTS AK (Virus Worm Ransom Trojan Spy Ad Key). Tip: "Malware Spreads Via Downloads" – Scan always.
Antivirus	Methods: Signature/Sandbox/Data/Heur/Real-time. Update VDF.	Polymorphic fail.	SSDHR (Signature Sandbox Data Heur Real). Tip: "Antivirus Scans Daily" – Prevent evolve.
Spam/HTTP	Spam: Unsolicited filter. HTTP: Plain vs HTTPS encrypt.	Gmail mark.	SHE (Spam HTTP Encrypt). Tip: "Spam Hides Exploits" – Lock icon check.
Firewall/Cookies	Firewall: Filter types network/host. Cookies: Track session/threats.	Fig 12.5 barrier.	FC (Filter Cookies). Tip: "Firewall Blocks Cookies Track" – Permission careful.
Hackers/Threats	Hackers: White/Black/Grey. Threats: DoS/DDoS/Snoop/Eaves.	Bot-Net DDoS.	WBG-DSE (White Black Grey DoS Snoop Eaves). Tip: "Hackers Break, Threats Deny" – Ethical fix.

Overall Tip: Use IPM-VWRTS AK-SSDHR-SHE-FC-WBG-DSE for full scan (5 mins). Flashcards: Front (term), Back (points + mnemonic). Print table for wall revision. Covers 100% chapter – easy for exams!

Key Terms & Processes - All Key

Expanded table 30+ rows; quick ref. Added advanced (e.g., Phishing, Bot-Net).

Term/Process	Description	Example	Usage
Malware	Malicious software	Virus	Damage
Virus	Spreads via host	ILOVEYOU	Infect files
Worm	Self-replicate	Storm Worm	Network
Ransomware	Encrypt/ransom	WannaCry	Block data
Trojan	Disguise legit	Backdoor	Trick install
Spyware	Track info	Usage data	Sell ads
Adware	Display ads	Pop-ups	Revenue
Keylogger	Record keys	Passwords	Leak
Antivirus	Detect/remove	Signature	Prevention
Spam	Unsolicited	Ads email	Tricks
HTTP	Plain protocol	News sites	Vulnerable
HTTPS	Secure encrypt	Banking	Protect
Firewall	Filter traffic	Network	Barrier
Cookie	Store browsing	Session	Track
White Hat	Ethical hacker	Fix flaws	Security
Black Hat	Malicious	Exploit	Crime
Grey Hat	Neutral	Fun hack	Challenge
DoS	Denial service	Flood	Overload
DDoS	Distributed DoS	Bot-Net	Multi
Snooping	Capture traffic	Sniffing	Analyze
Eavesdropping	Real-time intercept	Calls	Monitor
Phishing	Trick credentials	Fake email	Social eng
Bot-Net	Zombie network	DDoS	Control
Signature	Virus bytes	VDF	Detect
Sandbox	Virtual test	Behavior	Safe run
Heuristics	Pattern match	Code compare	Unknown
Buffer Overflow	Code inject	DoS	Intrusion
Supercookie	Malware disguise	Tracking	Threat
Zombie Cookie	Recreates deleted	Persistent	Threat
Hacktivist	Political hacker	Social change	Intent
Wiretapping	Old eavesdrop	Phones	Intercept
Rootkit	Hidden malware	Eavesdrop	Stealth

Tip: Examples memory; sort subtopic. Easy: Table scan. Added 10 rows depth.

Security Processes Step-by-Step

Step-by-step breakdowns of core processes, structured as full questions followed by detailed answers with steps. Visual descriptions for easy understanding; focus on actionable Q&A with examples from chapter.

Question 1: How does malware infect and how to prevent as in examples?

Answer:

Step 1: Distribute (download/spam).
Step 2: Infect (execute file).
Step 3: Damage (steal/block).
Step 4: Scan antivirus.
Step 5: Update software.
Step 6: Avoid unknown.

Visual: Chain – Download → Infect → Prevent (Antivirus). Example: WannaCry spread.

Question 2: What steps in antivirus detection (signature method)?

Answer:

Step 1: Update VDF.
Step 2: Scan files.
Step 3: Match signatures.
Step 4: Quarantine match.
Step 5: Remove malware.
Step 6: Report user.

Visual: Database match – File → Signature → Detect. Example: Virus bytes.

Question 3: How to use virtual keyboard against keyloggers (Fig 12.4)?

Answer:

Step 1: Load online.
Step 2: Random layout.
Step 3: Click keys mouse.
Step 4: Input sensitive.
Step 5: No key press log.
Step 6: Close session.

Visual: Shuffle keys – Random → Click → Secure. Example: Banking login.

Question 4: Process of firewall filtering (Fig 12.5)?

Answer:

Step 1: Define rules.
Step 2: Monitor incoming/out.
Step 3: Match packets.
Step 4: Block unauthorized.
Step 5: Allow trusted.
Step 6: Log events.

Visual: Wall barrier – Traffic → Filter → Pass/Block. Example: Student access limit.

Question 5: How does DDoS attack work?

Answer:

Step 1: Compromise Zombies.
Step 2: Install Bot.
Step 3: Activate Bot-Net.
Step 4: Flood target.
Step 5: Overload deny.
Step 6: Hard recover.

Visual: Network flood – Zombies → Target → Crash. Example: Global distributed.

Question 6: Steps to handle cookie permissions.

Answer:

Step 1: Site requests.
Step 2: Check third-party.
Step 3: Grant selective.
Step 4: Clear regularly.
Step 5: Avoid zombie.
Step 6: Privacy settings.

Visual: Data packet – Store → Track → Manage. Example: Ad follow.

Tip: Treat as FAQ; apply to figures. Easy: Q → Steps + Visual. Full Q&A for exam-like practice.

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