Patent ID: 7376626

Claim:
An information processing apparatus for performing a license obtaining process as a condition for a process for playing back content stored on a removable information recording medium, said information processing apparatus comprising: means for obtaining, from a removable information recording medium having stored thereon encrypted content data and a content key for decrypting the encrypted content data, identifier data (PID) containing a media ID as identification information of the removable information recording medium and a MAC, at least generated based on the media ID, as alteration verification data, and a product ID corresponding to a set of removable information recording media, means for transmitting the obtained PD and product ID as license request data to license providing system component entities via a network, and means for receiving license data for decrypting the encrypted content data with the content key, wherein the content key is obtained by decrypting an enabling key block (EKB) based on key data provided by a key distribution tree structure; and said information processing apparatus receives, from said license providing system component entities, service data and usage right information as license data, executes the enabling key block (EKB) on the basis of the license data, and decrypts the encrypted content data stored in said information recording medium.