Authentication codes: An area where coding and cryptology meet

TLDR: The purpose of authentication schemes is to add proof to a message that the message is authentic, i.e. it was not sent by an imposter and it has not been altered on its way to the receiver.

Abstract: Among many applications of cryptography, the use of authentication schemes is of great practical importance. The purpose of authentication schemes [3], [10] is to add proof to a message that the message is authentic, i.e. it was not sent by an imposter and it has not been altered on its way to the receiver. The imposter may replace an authenticated message by another message (substitution) or may just try to send his own message (impersonation). The aspect of secrecy could also be introduced here, but in many cases the receiver just wants to be sure that the message is genuine. Think for instance of offices that are communicating with each other.