Computer Science · Grade 12

Active learning ideas

Network Security Fundamentals

Active learning works for Network Security Fundamentals because students need to experience how defenses function in real time, not just memorize definitions. Hands-on labs and case studies help them see the limitations of individual tools, building critical judgment about layered security approaches.

• Ontario Curriculum Expectations
• CS.N.6
• CS.S.1

• 30–60 min
• Pairs → Whole Class
• 4 activities

Activity 01

• Escape Room
• 45 min · Pairs

Simulation Lab: Firewall Rule Setup

Students use an online firewall simulator to create rules blocking common ports like 23 for Telnet. Pairs test rules by sending mock traffic packets and observe blocked versus allowed connections. Debrief as a class on rule prioritization.

Explain the purpose of a firewall in protecting a network.

Facilitation Tip

During the Firewall Rule Setup lab, circulate to ask students to explain why they chose each rule, especially when blocking or allowing traffic. This reinforces their understanding of rule logic and default deny principles.

What to look for

Provide students with a scenario describing a small business network. Ask them to list three specific security measures they would implement, briefly explaining the purpose of each (e.g., 'Install a firewall to block unauthorized external access').

• Remember
• Apply
• Analyze
• Relationship Skills
• Self-Management

Activity 02

• Case Study Analysis
• 50 min · Small Groups

Case Study Analysis: Attack Vector Analysis

Provide real-world breach case studies like the Equifax hack. Small groups identify exploited vulnerabilities, map attack paths, and propose preventive measures using firewalls or IDS. Groups present findings on a shared digital board.

Analyze common network attack vectors and how they exploit vulnerabilities.

Facilitation Tip

For the Attack Vector Analysis case study, assign specific roles within groups so each student examines a different attack type before sharing findings with the class.

What to look for

Pose the question: 'Imagine a user clicks on a phishing link. Which network security component is most likely to detect or prevent the subsequent malicious activity, and why?' Facilitate a discussion comparing firewalls, IDS, and user awareness.

• Analyze
• Evaluate
• Create
• Decision-Making
• Self-Management

Activity 03

• Escape Room
• 60 min · Small Groups

Policy Design Challenge: Office Network

Teams design a security policy for a small office, specifying firewall configurations, IDS alerts, and user training. Incorporate key questions into the policy template. Peer review refines designs before whole-class vote on best elements.

Design a basic security policy for a small office network.

Facilitation Tip

In the Policy Design Challenge, provide a pre-made network diagram with labeled devices and ask students to annotate security measures directly on the diagram to connect theory to practice.

What to look for

Present students with a list of common network attacks (e.g., DDoS, Man-in-the-Middle, SQL Injection). Ask them to identify the primary type of security measure that would help mitigate each attack (e.g., Firewall, IDS, Input Validation).

• Remember
• Apply
• Analyze
• Relationship Skills
• Self-Management

Activity 04

• Escape Room
• 30 min · Pairs

Intrusion Hunt: Log File Review

Distribute sample network logs with simulated intrusions. Individuals or pairs scan for anomalies like repeated failed logins, then classify threats and recommend IDS responses. Share detections in a class gallery walk.

Explain the purpose of a firewall in protecting a network.

Facilitation Tip

During the Intrusion Hunt log file review, give students a limited time to analyze logs so they focus on identifying patterns rather than reading every entry.

What to look for

Provide students with a scenario describing a small business network. Ask them to list three specific security measures they would implement, briefly explaining the purpose of each (e.g., 'Install a firewall to block unauthorized external access').

• Remember
• Apply
• Analyze
• Relationship Skills
• Self-Management

A few notes on teaching this unit

Teach this topic by starting with concrete examples students can relate to, like their own school network or popular services they use. Avoid overwhelming them with too many attack types at once - focus on depth over breadth in early lessons. Use analogies carefully, as some can oversimplify complex systems. Research shows that students grasp security concepts better when they manipulate tools directly, so prioritize guided practice over lectures. Emphasize that security is a process, not a product, by showing how defenses evolve alongside new threats.

By the end of these activities, students should be able to identify common network vulnerabilities, explain how firewalls and intrusion detection systems mitigate risks, and draft basic security policies that address multiple attack vectors. They will also recognize that no single solution provides complete protection and design defenses accordingly.

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Watch Out for These Misconceptions

• During the Simulation Lab: Firewall Rule Setup, watch for students who believe firewalls scan all traffic for viruses and malware.

  Use the lab's mock virus injection to demonstrate that firewalls only filter based on rules, not content. Have students observe how 'safe' mock viruses pass through the firewall unless explicitly blocked by a rule they write.

• During the Case Study: Attack Vector Analysis, watch for students who think strong passwords alone can secure a network.

  In the case study, include a phishing scenario and SQL injection example. Ask students to map where passwords fit in each attack vector and identify other security measures needed to prevent these exploits.

• During the Policy Design Challenge: Office Network, watch for students who believe regular updates alone secure a network.

  Provide sample network logs showing both updated and unpatched systems being exploited. Have students analyze these logs during the challenge to see how updates mitigate some risks but miss others like social engineering or zero-day attacks.

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Methods used in this brief

• Escape Room
• Case Study Analysis