APPARATUS FOR DATA DISTRIBUTION, AND TERMINAL FOR DATA DISTRIBUTION

摘要

A contents database in which data of contents enciphered by a C key and the C key are stored is provided for a contents server. The contents data enciphered by the C key and the C key are enciphered by an M key and sent to a user machine. In the user machine, the contents data enciphered by the C key and the C key are stored in a storage device. Upon reproduction, the contents data enciphered by the C key and the C key from the storage device are sent to an enciphering/decoding processing unit and decoded and charging is performed in accordance with the C key. A DA code which dynamically changes with the elapse of time is added to the C key.