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oyster does have spending caps, but not the more complicated calcuations why? oyster is a stored value card the barrier where you tap-out calculates and takes

oyster does have spending caps, but not the more complicated calcuations why? oyster is a stored value card the barrier where you tap-out calculates and takes the money off the card instantly, and given the interaction time to get you through the barrier the computation is necessarily limited whereas a contactless card is effectively being a pointer to a bank account that can be charged at a later date for TfL there is a batch process at the end of the day which does that

zimpenfish 5y ago
> for TfL there is a batch process at the end of the day which does that Which can lead to some perplexing notifications from your bank at 0400 when it says you've just charged £N at A.N.Tube and it takes you a good three minutes before you realise it's not someone cloning your card but the journey you made 18 hours ago.