| 摘要 |
<P>PROBLEM TO BE SOLVED: To prevent the audition of contents by a person having no right of a looking and a listening, by distributing encrypting-content data that are difficult to decode by a third person. <P>SOLUTION: A new participating terminal device 2X transmits a participating request to a master terminal device 2 as a connection-destination candidate, while transmitting a public key for the participation for encrypting a content-decoding key. The master terminal device 2 as the connection-destination candidate receiving the public key for the participation from the new participating terminal device 2X generates an encrypting decoding key encrypting the content-decoding key by using the received public key for the participation, and transmits the encrypting decoding key to the new participating terminal device 2X. The new participating terminal device 2X decodes the encrypting decoding key received, by using a security key for the participation stored in a key storage means for the participation, and acquires the content decoding key. The distributing encrypting content data are decoded by using the content decoding key, and reproduction processing is conducted. <P>COPYRIGHT: (C)2007,JPO&INPIT |
