3 ms·
> Maybe that's not clear: the turnstile needs to connect to a server to check the QR. Need to only have one server, so some turnstiles will be relatively far fr
by woodruffw 2y ago
> Maybe that's not clear: the turnstile needs to connect to a server to check the QR. Need to only have one server, so some turnstiles will be relatively far from it. Latency.
Sure, but is this a serious design pressure? I've been on a lot of EU train and trolley networks that have a POS terminal on the train for direct sales, which are already doing networking both for the card transaction and to issue the ticket.
(Again to be clear: I'm not saying a QR is better. But I don't think connectivity is a unique problem, since systems that use NFC without tying into payment cards are almost certainly using connectivity to make up for the lack of tamper resistance.)