Assuming NFC works the same way Lockheeds RFID system works - you havea tag ID which is read against a back-end DB which holds the tags value, where the tag/card holds no value data itself, how can this work with SF Transit police checking cards?
Assume you dupe your friends card, then both go through the turn style -- wont the system error as the system will say that the second read is either "tagged for exit" or maybe it will read it as a 90-minute transfer read?
If you get stopped by the transit police, assuming you got through the turn style, you'd have to have a valid ticket/clipper on you, no?
It's tag only so if you tag again because lets say you were unsure you tagged, the second tag is disregarded, it's the same idea if I ride a bus but have to transfer I tag again but I don't pay again. It's just to verify I've tagged once since getting on. Can't say I've ever seen transit police but could be the buses I ride, and their's a fine for not being able to show you paid, but buses and muni is just tag as you get on. So theirs a risk of course.
Usually the reader has a local log of the last few cards read. If it detects the same card again within a certain time window it assumes it either read it twice - or two people are sharing a card - and ignores the second read
Assume you dupe your friends card, then both go through the turn style -- wont the system error as the system will say that the second read is either "tagged for exit" or maybe it will read it as a 90-minute transfer read?
If you get stopped by the transit police, assuming you got through the turn style, you'd have to have a valid ticket/clipper on you, no?