At least in the U.S., during the 1970s and 1980s (and likely before), many tollways and other ticket-based systems used to use publicly distributed and collected "IBM-style" punched cards along with automated equipment. When someone entered a toll way, for example, one would receive a punched card which would be handed to an attendant at the exit. Presumably, the cards could be fed into a computer to, among other things, produce a report of how much different portions of the tollway were used. If toll collectors kept stacks of cards in order, and placed a "time of day" card onto the stack every hour, such reports could also include information about rush-hour and non-rush-hour usage compared.

Did such systems make any effort to guard against the possibility that a malicious person with a card punch might alter cards so as to not only supply meaningless information, but perhaps disrupt system operations in more serious ways, such as by having a few consecutive motorists at a toll booth submit a JCL control card followed by some cards that were programmed to run malicious code? Were there ever any incidents of them being attacked in such a fashion? Or were the set of people with the knowledge that would be needed to perform such an attack and the set of people who would want to carry out such an attack sufficiently disjoint that no such attacks were ever attempted?

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    As I recall it, the card was read at the exiting toll booth to get the amount owed (and perhaps compared with the printed entrance), meaning an error would be generated at that time (and the toll based on the printed info). I figured it was more a check on the honesty of the toll taker so the cash drawer tally would match the card tally. But I have no clue what was done with the cards beyond my picking one up and handing it over with the toll.
    – Jon Custer
    Sep 30, 2020 at 17:50
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    @JonCuster: Thanks for the link. Although tool booths are the place I most often saw such cards, I've also encountered punched cards used for similar purpose in such a wide range of other venues that the phrase "Do not bend, fold, multilate, or spindle" became as much part of the American lexicon as the "This bag is not a toy" warning one finds everywhere today.
    – supercat
    Sep 30, 2020 at 18:28
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    "Little Bobby Tables" happens because user data is inserted into code that is then interpreted. I'm thinking that was anywhere from uncommon to exceedingly rare in mainframes of the punched-card era, but I look forward to knowledgeable answers from those who were there. Oct 1, 2020 at 4:55
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    No, because punch cards didn’t use SQL. Oct 10, 2020 at 17:42


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