So the machine connected to your Windows XP tills has internet access and/or external storage enabled. Of course that's not safe....if I said "not connected to a network" would that be better?
Nope. You just flipped one of your caveats: no internet connectivity.
I only specified networking.
Its also how Target was attacked. Their registers are networked yet there was a hole from the internet to their corporate net. That hole was through their HVAC control system.
The Tl;Dr. Is that you design a secure system, so that if one part fails, the whole system doesn't fall like a house of cards. Security through layers.
You can say that... but I think GP's point is that there's an obvious behavioral pattern to that, which is less data mining of your sales info and customer's buying habits, compared to the sometimes unobvious but major downside of the terminals being hacked. I think we've seem what choices businesses make when presented with the obvious upside over the poorly understood downside.
