Patent attributes
The present invention relates to a content distribution server or the like, capable of more surely preventing an unauthorized use of a content. Content distribution servers 2 and 3 are arranged to be connectable via a telecommunication circuit to a user terminal device, and include: a distribution-content storing section 14 for storing a distribution content file composed of: content data; and a regulatory program including a first key for regulating reproducing the content data; a key storing section 15 for storing a second key which forms a pair with the first key; a key generating section 34 for generating, when receiving the terminal identification information transmitted from the user terminal device, a third key including the received terminal identification information and information of the second key; and transmitting controllers 16 and 34 for transmitting the third key to the user terminal device. When the distribution content file is opened on the user terminal device, the regulatory program transmits the terminal identification information to the content distribution servers 2 and 3 before the content data are reproduced.
