Abstract: A client receives encrypted content from content server. The header of the content includes license-identifying information for identifying a license required to utilize the content. The client requests a license server to transmit the license identified by the license-identifying information. When receiving the request for a license, the license server carries out a charging process before transmitting the license to the client. The client stores the license received from the license server. The stored license serves as a condition for encrypting and playing back the content. As a result, content can be distributed with a high degree of freedom and only an authorized user is capable of utilizing the content.

Abstract: A client receives encrypted content from content server. The header of the content includes license-identifying information for identifying a license required to utilize the content. The client requests a license server to transmit the license identified by the license-identifying information. When receiving the request for a license, the license server carries out a charging process before transmitting the license to the client. The client stores the license received from the license server. The stored license serves as a condition for encrypting and playing back the content. As a result, content can be distributed with a high degree of freedom and only an authorized user is capable of utilizing the content.

Abstract: A client receives encrypted content from content server. The header of the content includes license-identifying information for identifying a license required to utilize the content. The client requests a license server to transmit the license identified by the license-identifying information. When receiving the request for a license, the license server carries out a charging process before transmitting the license to the client. The client stores the license received from the license server. The stored license serves as a condition for encrypting and playing back the content. As a result, content can be distributed with a high degree of freedom and only an authorized user is capable of utilizing the content.

Abstract: A client receives encrypted content from content server. The header of the content includes license-identifying information for identifying a license required to utilize the content. The client requests a license server to transmit the license identified by the license-identifying information. When receiving the request for a license, the license server carries out a charging process before transmitting the license to the client. The client stores the license received from the license server. The stored license serves as a condition for encrypting and playing back the content. As a result, content can be distributed with a high degree of freedom and only an authorized user is capable of utilizing the content.

Abstract: A portable disc player has a casing. In the casing, there are enclosed: disc rotation driving means for rotating an optical disc; an optical head which is arranged so as to be movable in the radial direction of the optical disc; a signal processing section for executing a predetermined signal process to a signal which has been read out by the optical head; and control means for controlling the operations of the rotation driving means, the optical head, and the signal processing section on the basis of an input from an X-Y device and trigger buttons. A display unit comprising an outer cover on which an LCD display is arranged is rotatably attached to the casing.