... of this second kind of attacksare the alteration of a piece of evidence in a criminal trial, or the manipulation of public opinion through the use of falsewiretapping. Often, for the sake of ... to the prohibitive cost of the professional equipment—has become quite a widespreadpractice. In addition to the ease of such manipulations, the problem of the diffusion of unauthorized copies of ... the content producer (CP), which is the entity that publishes ordistributes the legitimate and authentic copies of the originalaudio content. On the other hand, there is the CU, which is the consumer...