Mobile terminal, encrypted contents reproduction method and plaintext data generation method employed for the same

摘要

A mobile terminal adapted to reproduce an encrypted contents file stored in a predetermined storage area as an alert of an incoming call includes: a storage section for holding first plaintext data corresponding to a head portion of the encrypted contents file; decryption means for decrypting the encrypted contents file to generate second plaintext data; reproduction means for reproducing the first and second plaintext data; and authentication means for performing authentication processing related to use of the encrypted contents file. The reproduction means reproduces the first plaintext data and in succession to reproduction of the first plaintext data reproduces the second plaintext data when the mobile terminal receives a call. The authentication means performs the authentication processing simultaneously and in parallel with the reproduction of the first plaintext data by the reproduction means.