Patent ID: 7370205
Filing Date: 2008-05-06
Classification: G06F

Abstract:
1. A content distribution system including a distribution server and a terminal device connected through a network, wherein said distribution server comprises: embedding means for converting user identification information and a storage definition flag into watermark information through spreading modulation and embedding the watermark information in content, the user identification information uniquely assigned to said terminal device, the storage definition flag having a state previously set on said terminal device side; encryption means for encrypting said content having said watermark information embedded therein; and transmitting means for transmitting said encrypted content to said terminal device through said network, and said terminal device comprises: reception means for receiving said content; extraction means for extracting said user identification information and said storage definition flag from said watermark information embedded in said content; decryption means for decrypting said encrypted content depending on the existence of said user identification information; judgment means for judging, based on the state of said storage definition flag, whether said decrypted content should be encrypted before being stored; and storage means for storing said content having said watermark information embedded therein.