Cybersecurity II: Protection Methods – SS1 Digital Technologies Lesson Note (Second Term)

Cybersecurity protection is the set of methods used to keep a computer and its data safe from viruses, hackers and scammers.

• Antivirus software: detects and removes malware.
• Firewalls: control the traffic entering and leaving a network or computer.
• Strong passwords and two-factor authentication: protect user accounts.
• Defence in depth: using several of these methods together.

Behavioural objectives

By the end of the lesson, students should be able to:

1. explain what “defence in depth” means;
2. describe how an antivirus works (scanning, signatures and quarantine);
3. state the difference between an antivirus and a firewall, and name the two types of firewall;
4. create a strong password using the rules taught;
5. explain how two-factor authentication works and name other forms of it.

What is cybersecurity protection?

Cybersecurity protection is the combination of tools and habits that defend a computer, a network and user accounts from attack.

• Link to the last lesson: the last lesson covered the “bad guys” (viruses, hackers and scammers). This lesson covers the “good guys”.
• House example: if your computer is a house, protection is the high fence, the strong gate, the security guard and the secret vault inside.
• Layers: no single method is enough, so we use several layers of security.

What is defence in depth?

Defence in depth is the use of several layers of security so that if one layer fails, another still protects the system.

• Layer 1, firewall (the security guard): checks the traffic coming in and going out.
• Layer 2, antivirus (the doctor): finds and removes harmful files.
• Layer 3, strong passwords and 2FA (the secret keys): stop strangers from opening your accounts.

What is antivirus software?

An antivirus is a program that acts like a digital immune system by detecting, blocking and removing malicious software (malware).

How does an antivirus work?

• Scanning: it looks through every file you download and every flash drive you plug in.
• Signatures: it keeps a “Most Wanted” list of known virus codes. A file that matches a code on the list is stopped at once.
• Quarantine: a suspicious file that is not certain to be harmful is moved to a “digital jail”, so it cannot harm the rest of the computer.

What are examples of antivirus software?

• Avast: a free and paid antivirus program.
• Norton: a paid security program.
• McAfee: a paid security program.
• Windows Defender: the antivirus built into Windows.

Teacher’s tip: Remind students that an antivirus is only as good as its last update. New viruses appear every day, so the “doctor” must keep learning.

What is a firewall?

A firewall is a network security system that monitors and controls incoming and outgoing network traffic based on a set of safety rules.

• What it checks: the traffic moving in and out through the internet.
• Street example: the internet is a busy street, and the firewall sits at your front door.
• Its action: it checks the “ID” of every piece of data trying to enter. Data from a hacker or dangerous source is blocked.

What are the types of firewall?

There are two types of firewall: software firewalls and hardware firewalls.

• Software firewalls: programs built into your operating system (OS), such as Windows Firewall.
• Hardware firewalls: physical devices, often found in schools or offices, that protect many computers at once.

What is the difference between an antivirus and a firewall?

An antivirus looks at the files inside your computer, while a firewall looks at the traffic entering and leaving it.

How do you create a strong password?

A strong password is one that is long, mixed and impossible for other people to guess.

• The problem: many people use easy passwords such as “password123” or “firstname1234”.
• The danger: hackers use programs that try huge numbers of simple passwords very quickly.

What are the rules for a strong password?

1. Length: use at least 12 characters.
2. Mix it up: use UPPERCASE letters, lowercase letters, numbers (123) and symbols (!@#).
3. No personal information: do not use your name, birthday or school name.
4. The “passphrase” trick: use a sentence that only you know, not a single word.

What is two-factor authentication (2FA)?

Two-factor authentication (2FA) is a login method that asks for two different proofs of identity before it opens an account.

• Why it is needed: even a strong password can be stolen.
• Another name: multi-factor authentication (MFA), which may use more than two proofs.

How does 2FA work?

1. You enter your password (something you know).
2. The app sends a code to your phone (something you have).
3. You type in the code to finish logging in.

A hacker who steals your password still cannot log in, because the hacker does not have your phone to see the secret code.

What are other forms of 2FA?

• Biometrics: fingerprints or Face ID, which use something about your body.
• Security keys: physical USB keys you plug in to log in to an account.

Classroom discussion

• The golden rule: never use the same password for two different accounts. If a hacker gets your TikTok password, you do not want the hacker in your bank account too.
• Discussion: why do some people find 2FA “annoying”? Is the extra 10 seconds worth the safety?

Evaluation

1. What is the difference between an antivirus and a firewall?
2. Explain the “quarantine” feature in an antivirus.
3. Rewrite this weak password to make it strong: nigeria2026.
4. Why does 2FA give extra protection against hackers?

Assignment

In your notebook, write a short note on two-factor authentication. Explain how it works with a password and a phone code, and name two other forms of 2FA.