| 摘要 |
A method and system for distributing digital documents ensures security by encrypting pages, element by element, when the document is downloaded onto a terminal. After the document (w20) is opened in a console, reading begins by activating an initialization request containing a single document identifier (id1, id2) to a control server (w21), which returns a ticket containing current rights associated with the single identifier (w25, w26, w27, w22). When the current rights allow reading, the end of loading each XHTML page triggers requests for decryption, sending the encrypted elements to the control server, which returns decrypted elements unscrambled. The multimedia contents are encrypted by a key generated by the control server or are filtered by a transformation matrix. Due to an encrypted cache within the console, the document can be restored, in partially or permanently disconnected mode, by storing the decrypted elements in a crypted cache onto a terminal. |
