My Wi-fi and public Wi-fi?
QI note that when talking about getting online you sometimes warn against using public Wi-fi connections. I wonder why that is? I think I appreciate that Wi-fi hotspots without passwords are a bad idea because anyone can log on to them. But what’s the problem with using one in a cafe or library, say – where you have to ask for the password at the counter? Why would using such a connection be any less safe than using my own Wi-fi at home? Is there a difference I’m not understanding? Nick Duffy
AThis is a good question, not least because the answers aren’t necessarily all that obvious – even if the received wisdom is consistent. Fundamentally, the problem boils down to control and trust. Or rather, as the user, your lack of one or both.
Assuming all is well then, when you’re at home, you are in full control of your router. By that we mean you know the name of the wireless network it transmits (also known as the Service Set Identifier, or SSID) and the password, and you can change either at any time. The only person who can see data travelling to and from the router is you, or other authorised members in your home.
But when you connect to a public Wi-fi hotspot, all of that goes out of the window. Certainly, connecting to a Wi-fi hotspot where you’ve had to ask a staff member for the SSID and password is ‘better’ than connecting to a random, password-less signal – but can you be sure every single person with access to the router is trustworthy? Even if you have faith in the counter staff, it is unlikely that you’ll know who else might have access to the equipment running the hotspot.
Any data that is passed from your computer to the Wi-fi hotspot could, in theory, be accessed by those controlling the router that provides it – and unlike at home, those people are not you or your family.
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