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I would like to have a maximum value $100 offline capable smart card issued by the government. It's, of course, not physically possible to prevent double spend
by avidiax 3y ago
I would like to have a maximum value $100 offline capable smart card issued by the government.
It's, of course, not physically possible to prevent double spending of an offline smart card (just as it's not physically possible to prevent duplicating a $20 bill), but I think it could be made difficult enough, just as is done with physical currency.
People would generally have one of these cards, and use them to make change in cash transactions, or make small purchases outright.
The size of a credit card means that this isn't much more of a money laundering concern than a physical $100 bill is, and if the protocols have tight latency requirements, then these cards can't be used remotely, either. Criminals could punch the chip out (just like a nano SIM), but that's still order of magnitude the same as physical currency.