Recording medium that can prevent fraudulent usage of content and content rental system using such recording medium

摘要

When reproduction is requested from an external connection apparatus in a state where a recording medium (10) is loaded in a reader (30), a read operation is initiated. A content request is issued to the recording medium (10). On the part of the recording medium (10), after the request is received, a voltage measurement unit (109) measures the voltage of an accumulation unit (110). It is assumed that the allowed period of reproduction has expired when the measured value is below a predetermined value. An expiration notification is issued to the content reader (30). Then, the process ends. Thus, the content recorded in the recording medium can be reliably prevented from being used improperly after the usage expiration term.