Earlier quoted context omitted.
What about a classical mechanical key? I am referring to a laser cut key, the type that can't be easily lock picked, other than in Hollywood movies. The problem is relay theft, where thief's relay the signal of your fob key inside the house to the car via a simple antenna and amplifier system. Cryptographically signing won't help. However, this can be fixed by adding a motion sensor that makes key fobs go into a slee…
This is two factor auth but when the "thing you own" is the standard case. I don't get why it's not a keypad and relay though. Sounds like a complex solution to a fairly simple problem. I might be missing something though. Edit - ah it's intended to work with many other options like controlling indicators or wipers or something - so you choose some pattern that is your password.
I think you're asking exactly the right question though - how is all this not just a more complex, less secure, shittier version of a keypad that you enter a 4-6 digit code on?