An information processing device, comprising: a data processing unit configured to read out and reproduce data recorded in an information recording medium, and data stored in a local storage unit which is different from the information recording medium, wherein the information recording medium is any one of an information recording medium of a version 1 and an information recording medium of a version 2 which are required for different data processing in reproduction processing; wherein the data processing unit, executes processing of selecting subsequent data corresponding to content recorded in the information recording medium from the local storage unit, as reproduction target data, executes directory name calculation processing; in which a conversion function f1 corresponding to the version 1 is applied to configuration data of a root certificate recorded in the information recording medium, in a case where the information recording medium of the version 1 is mounted on the information processing device, and executes directory name calculation processing in which a conversion function f2 corresponding to the version 2 is applied to configuration data of a root certificate recorded in the information recording medium, in a case where the information recording medium of the version 2 is mounted on the information processing device, at the time of performing the processing of selecting the reproduction target data, and selects data which is recorded in a directory having a calculated directory name from the local storage unit, as the reproduction target data, wherein the directory name is a directory name of a studio and version directory. a data processing unit configured to read out and reproduce data recorded in an information recording medium, and data stored in a local storage unit which is different from the information recording medium, wherein the information recording medium is any one of an information recording medium of a version 1 and an information recording medium of a version 2 which are required for different data processing in reproduction processing; wherein the data processing unit, executes processing of selecting subsequent data corresponding to content recorded in the information recording medium from the local storage unit, as reproduction target data, executes directory name calculation processing; in which a conversion function f1 corresponding to the version 1 is applied to configuration data of a root certificate recorded in the information recording medium, in a case where the information recording medium of the version 1 is mounted on the information processing device, and executes directory name calculation processing in which a conversion function f2 corresponding to the version 2 is applied to configuration data of a root certificate recorded in the information recording medium, in a case where the information recording medium of the version 2 is mounted on the information processing device, at the time of performing the processing of selecting the reproduction target data, and selects data which is recorded in a directory having a calculated directory name from the local storage unit, as the reproduction target data, wherein the directory name is a directory name of a studio and version directory.