System for preventing unauthorized use of digital content

摘要

A system for preventing unauthorized use of digital content that can prevent unauthorized use of digital content and can reliably collect a charge for secondary use is provided. The system for preventing unauthorized use may include: a distributing recording medium alpha on which a content file having header information "A" and a data body "B" is recorded in a state of lacking play information "A1" indispensable for playing the data body "B" included in the header information a; a management center managing use of the content file on the distributing recording medium alpha and which can deliver the prepared play information "A1" of the header information "A" as piece data via a communication line beta; and a digital content playing device which is a device used for playing the content file on the distributing recording medium alpha and has a function of communicating via the communication line beta with the management center.