This invention provides a recording medium supportable device such as a library
device (50), which authenticates each recording medium by identification
information such as serial number and controls the recording medium by a command
based on radio communication. In this case, a communication identifier like a session
identifier corresponding to the identification number is set and provided and the
communication identifier is included in a command at the time of execution of control,
so that only a specified recording medium to be controlled carries out an operation
corresponding to the command. When authenticating the recording medium, the identification
information, which is proper information such as serial number, is confirmed through
reliable communication using successive communication identifiers, and reliable
authentication of the recording medium is carried out by several stages of communication.