DIGITAL DATA TRANSMITTING METHOD AND APPARATUS, DIGITAL DATA REPRODUCING METHOD AND APPARATUS, DIGITAL DATA COPYING METHOD AND APPARATUS, DATA RECORDED MEDIUM, AND DIGITAL DATA STORING/REPRODUCING METHOD

摘要

A shop, a cabled network, a portable telephone network or a satellite network is used as means for distributing the a contents in a content server to user units. The contents are encrypted and compression encoded. Associated information including information on charging and charging conditions is also transmitted. Each user unit performs decryption and decompression to reproduce the contents and performs charging at the time of reproduction. Delivery of the contents is free of charge and the reproduction is charged. The charging is carried out using prepaid data representing the number of possible reproductions and the possible reproduction time. At the time of pay reproduction, an autheticating/charging server authenticates the user apparatus and delivers a key required for decryption.