| 摘要 |
<P>PROBLEM TO BE SOLVED: To distribute rental contents through a network. <P>SOLUTION: Disclosed are an information reproducing method of reproducing an information recording medium where ciphered contents having been purchased through the network, purchase style information showing whether the contents is rented with a reproduction time limit or sold without reproduction time limit, and control information for reproducing rental/sell contents are recorded. The purchase style information is discriminated to receive reproduction time limit information from an authentication server and determines whether the reproduction time limit has expired when the content is rented; when the reproduction time limit has not expired, it is determined whether a title key is already cached and when the title key is cached, the contents are reproduced immediately, but when not, on the other hand, a key is requested from a key managing server to reproduce the ciphered contents by using the key sent from the key managing server. <P>COPYRIGHT: (C)2006,JPO&NCIPI |
