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A comment on The tiny chip that powers Montreal subway tickets. Parent comment

Re:The tiny chip that powers Montreal subway tickets by kevincox on Monday June 24, 2024 @06:48AM (#40774452)
You can fail open. The QR code contained a signed ticket ID and expiry. You locally validate the signature and expiry and remotely attempt to validate reuse. If the remote validation is slow or fails just accept the ticket and log it.
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Re:The tiny chip that powers Montreal subway tickets by rswail on Wednesday June 26, 2024 @01:41AM (#40796762)
That is what happens, however it exposes the transit company to a risk that many of them aren't willing to accept.
[ Parent | on HN ]