Public Wi-Fi & VPNs
Learn how public networks work, what HTTPS protects, when a VPN is useful and why online privacy requires more than one tool.
Is public Wi-Fi dangerous?
Public Wi-Fi is convenient. You'll find it in cafés, hotels, airports and shopping centres.
Using public Wi-Fi doesn't automatically expose your passwords or personal information. Modern websites usually use HTTPS to encrypt information exchanged with your browser.
You might connect to an untrustworthy network, visit an insecure website or encounter a fraudulent login page.
What should you watch out for?
Verify the correct Wi-Fi network name with the venue rather than connecting to the first familiar-looking network.
Your browser already provides protection.
HTTPS uses TLS encryption to protect information travelling between your browser and the website you're visiting.
Opens an HTTPS website
Protects the contents of your communication while in transit
Receives your encrypted connection
HTTPS doesn't prove a website is trustworthy. Scam websites can also have valid HTTPS certificates.
What does a VPN actually do?
A Virtual Private Network creates an encrypted connection between your device and a VPN server.
Connects to your VPN provider
Protects traffic travelling between your device and the VPN server
Forwards your traffic towards its destination
Usually sees the VPN server's public IP address
A VPN can prevent local network operators from directly inspecting traffic inside the VPN tunnel.
However, the VPN provider becomes another organisation you must trust.
What a VPN doesn't do.
A VPN improves privacy in certain situations. It doesn't guarantee anonymity or complete security.
Who are you trusting?
When you use a commercial VPN, some visibility shifts from your internet provider or local network to your VPN provider.
A free VPN isn't necessarily unsafe, and a paid VPN isn't automatically trustworthy. Evaluate the provider.
What about using mobile data?
Your phone's mobile connection provides an alternative to unfamiliar public Wi-Fi networks.
Using your phone as a personal hotspot can be convenient when travelling, although mobile providers can still observe some connection information.
Protect your personal hotspot with a strong password and disable it when you no longer need it.
Are VPNs and Tor the same?
No. A typical VPN routes your traffic through a provider's VPN server.
Tor routes traffic through multiple relays and is designed to provide stronger anonymity properties in certain circumstances.
Neither technology guarantees complete anonymity. Combining them doesn't automatically make you safer.
We'll explore Tor separately in CyberCumbria's more advanced guides.
Your public Wi-Fi safety checklist.
HTTPS, software updates and sensible browsing habits are important whether or not you use a VPN.
Breaches & Recovery.
Our final lesson explores data breaches, compromised accounts and how to recover when something goes wrong.