Information processing apparatus, content providing system, information processing method, and computer program

A content providing system, comprising:

• a user device configured to transmit media information to a service server, and receive transmission data from said service server;
• said service server configured to transmit the transmission data in response to receipt of the media information from said user device;
• and
• a key management server configured to manage a unit key that is used to encrypt the transmission data, wherein
• said service server receives the media information from said user device, and transmits the media information and a transmission data identifier to said key management server,
• said key management server encrypts a unit key stored so as to be associated with the transmission data identifier with a cryptographic key stored so as to be associated with the media information, and transmits the generated encrypted unit key to said service server, and
• said service server transmits the encrypted unit key acquired from said key management server and the encrypted transmission data to said user device.

An information processing apparatus that serves as a key delivery server that delivers a key to a service server that transmits transmission data in response to receipt of media information from a user device, the apparatus comprising:

• a cryptographic key database that stores the media information and a cryptographic key that is set for the media information such that the media information and the cryptographic key are associated with each other;
• a transmission data-use cryptographic key database that stores a transmission data identifier and a unit key such that the transmission data identifier and the unit key are associated with each other;
• and
• a control section configured to acquire, from said cryptographic key database, the cryptographic key that is set for the media information and associated with the media information received from the service server, acquire the unit key associated with the transmission data identifier received from the service server from said transmission data-use cryptographic key database, encrypt the acquired unit key with the cryptographic key that is set so as to be associated with the acquired media information, and transmit the encrypted unit key to the service server.