Applications
Thus, a random function can be considered to map each input independently at random to any one of the possible outputs. Viewed this way it is an idealization of a cryptographic hash function. A random function is a useful building block in enabling cryptographic protocols. However, there are scenarios where it is not possible for mutually distrustful parties to agree on a random function (i.e., coin flipping is impossible). Therefore, cryptographers study models which explicitly allow for the use of a random function or a related object. See random oracle model, common reference string model.
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