The keyword not mentioned here is one-way function. Cryptography is for the most part based on candidates for one-way functions: functions that are easy to perform on any input but difficult to undo on average. The existence of such a function would imply that P is not NP but the converse doesn't hold.
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The keyword not mentioned here is one-way function. Cryptography is for the most part based on candidates for one-way functions: functions that are easy to perform on any input but difficult to undo on average. The existence of such a function would imply that P is not NP but the converse doesn't hold.