Encoding and recording apparatus, playback apparatus, and program

摘要

The present invention relates to an encoding and recording apparatus, a playback apparatus, and a program which solve the possibility of a capacity shortage of a protected area accompanying an increase in an information amount and the number of content keys. It is configured such that an encoded user identifier is recorded in a protected area of a key storage medium. The encoded user identifier is fixed information, and has the characteristic in which a data amount is not increased in connection with a utilization form. Therefore, a capacity shortage of the protected area is not brought about.