Module 3: Network Security Basics

Understanding Network Security

Network security involves protecting the usability, reliability, integrity, and safety of your network and data. Whether at home, in a coffee shop, or at work, understanding network security basics helps protect your devices and information from unauthorised access.

What is a VPN (Virtual Private Network)?

A VPN creates a secure, encrypted tunnel between your device and the internet. Think of it as a private highway for your data.

How VPNs Work: They encrypt all your internet traffic and route it through a remote server, masking your IP address and location.

When to Use a VPN:

✅ On public Wi-Fi networks (cafes, airports, hotels)
✅ When accessing work resources remotely
✅ When you want to protect your privacy online
✅ When traveling internationally

What VPNs DON'T Do: They don't make you completely anonymous, don't protect against phishing, and don't prevent malware infections. They're one layer of security, not a complete solution.

Firewalls: Your Network's Gatekeeper

A firewall is security software or hardware that monitors incoming and outgoing network traffic and blocks or allows data based on security rules.

Types of Firewalls:

Software Firewalls: Built into your operating system (Windows Defender Firewall, macOS Firewall)
Hardware Firewalls: Built into your router, protecting all devices on your network

Best Practice: Enable BOTH your OS firewall AND your router's firewall for layered protection.

Wi-Fi Security: Protecting Your Wireless Network

At Home:

Use WPA3 encryption (or WPA2 if WPA3 isn't available)
Change default router passwords immediately
Use a strong Wi-Fi password (12+ characters)
Hide your SSID (network name) if possible
Keep router firmware updated
Disable WPS (Wi-Fi Protected Setup) - it's insecure
Consider a guest network for visitors

On Public Wi-Fi:

❌ NEVER access banking or sensitive accounts without a VPN
❌ Avoid "open" networks with no password
✅ Always use a VPN on public networks
✅ Turn off file sharing and AirDrop
✅ Forget the network after use
✅ Use your phone's hotspot when possible

HTTPS vs HTTP: The Padlock Matters

HTTP (Hypertext Transfer Protocol): Data sent in plain text - anyone can intercept and read it.

HTTPS (HTTP Secure): Data is encrypted using SSL/TLS - much safer.

Always check for:

🔒 Padlock icon in the address bar
"https://" at the beginning of the URL
Valid certificate (click the padlock to check)

Warning: HTTPS only encrypts the connection - it doesn't guarantee the website is legitimate! Phishing sites can also use HTTPS.

Mobile Security: Your Phone is a Target

With 5G networks and mobile banking apps becoming standard across Australia, your smartphone has become a primary target for attackers. Most Australians now access banking, myGov, and work emails from their phones.

Essential Mobile Security Practices:

Keep your OS updated: Install iOS/Android updates promptly - they patch critical security vulnerabilities
Only download from official stores: App Store (iOS) or Google Play Store (Android) - third-party app stores often contain malware
Review app permissions regularly: Does that flashlight app really need access to your contacts and location?
Use biometric authentication: Face ID, fingerprint, or iris scan adds strong protection
Enable "Find My" features: Find My iPhone or Find My Device helps locate/remotely wipe lost phones
Be cautious of public charging stations: "Juice jacking" attacks can steal data through USB ports - use your own charger or power-only cables
Use mobile security apps: Consider reputable antivirus/security apps from known brands
Enable automatic lock: Set your phone to lock after 30-60 seconds of inactivity

Australian Mobile Banking Security:

Most major Australian banks (CommBank, NAB, ANZ, Westpac) require multi-factor authentication
Never save banking passwords in your browser or notes app
Use the official bank app rather than mobile browser for transactions
Enable transaction notifications to detect unauthorised activity immediately
Be wary of apps asking for banking credentials - legitimate apps won't ask for your full password

QR Code Scams - Growing Threat in Australia:

Scammers place fake QR codes over legitimate ones (parking meters, restaurant menus, payment terminals)
Always verify the URL before entering payment details after scanning
Be suspicious of QR codes in unexpected places or on stickers that look recently applied
Use your phone's camera to preview the URL before opening
For payments, verify the business name matches before proceeding

SMS and Phone Scams Targeting Australians:

Flubot malware: SMS messages claiming missed deliveries with malicious links
ATO scam calls: Threatening calls claiming you owe tax money
Tech support scams: "Microsoft" or "Telstra" calling about computer problems
NBN scams: Fake NBN technicians requesting remote access

Remember: Government agencies like ATO, Services Australia, and myGov will NEVER call demanding immediate payment or ask for passwords/PINs over the phone.

Key Takeaways

🔐 Use VPNs on public Wi-Fi and for remote work
🔐 Enable firewalls on all devices
🔐 Secure your home Wi-Fi with WPA3 and strong passwords
🔐 Always prefer HTTPS websites
🔐 Keep network devices updated
🔐 Never trust open public Wi-Fi without protection
🔐 Protect your mobile devices - they're your most vulnerable access point
🔐 Be wary of QR codes from unknown sources

🌐 Module 3: Network Security Basics

📚 Training Content