3 ms·

There are a lot of credit card machines where the purchases swipes the card themselves. Since the speed that people swipe is going to be variable, it can't be

by prewett 17y ago

There are a lot of credit card machines where the purchases swipes the card themselves. Since the speed that people swipe is going to be variable, it can't be too hard to read a card without knowing the speed. (Like, say, putting 10101010 at the beginning, which you could use for calibration) So I'm not sure how a random speed helps things. Maybe ATM bits aren't encoded like credit cards?

praptak 17y ago
"Since the speed that people swipe is going to be variable, it can't be too hard to read a card without knowing the speed." The speed just has to be fairly constant within a single swipe - then you can adjust for it. It usually is when humans do that - human hand has quite an inertia. The security feature on ATMs makes it vary wildly within a single swipe.