Patent ID: 7353541

Claim:
A multimedia content delivery system for sending predetermined content data from an information sending apparatus to an information receiving apparatus, wherein the information sending apparatus comprises: means for holding first identification information with an individual key, wherein the first identification information identifies the information sending apparatus and the individual key is unique to the information sending apparatus, and further wherein the first identification information with the individual key is encrypted by a distribution key that is unique to the information receiving apparatus; means for adding second identification information to the content data, wherein the second identification information is identical to the first identification information; means for encrypting the second identification with the content data by a content key; means for encrypting the content key by the individual key; means for sending the encrypted first identification information with the individual key, the encrypted second identification information with the content data, and the encrypted content key to the information receiving apparatus; and wherein the information receiving apparatus comprises: means for holding the distribution key; means for receiving the encrypted first identification information with the individual key, the encrypted second identification information with the content data, and the encrypted content key to the information receiving apparatus; means for decrypting the encrypted first identification information with the individual key using the distribution key to acquire the first identification information and the individual key; means for decrypting the encrypted content key using the individual key to acquire the content key; means for decrypting the encrypted second identification information with the content data by using the content key to acquire the second identification information and the content data; and means for comparing the first identification information with the second identification information.