Method and apparatus for the transmission of digital data, a method and apparatus for reproducing digital data, a method and apparatus for the copying of digital data, data as well as a method for storing and reproducing digital data

摘要

A shop, a cabled network, a portable telephone network or a satellite network is used as means for distributing the 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 authenticating/charging server authenticates the user apparatus and delivers a key required for decryption.