Patent attributes
An information processing apparatus has an authentication & key exchange unit, a contents receiver, a contents decryption unit and a contents confirmation request unit. The authentication & key exchange unit performs authentication & key exchange processing by using a given protocol with the communication apparatus and generates a first key shared with the communication apparatus. The contents receiver receives encrypted contents obtained by encrypting the contents with a second key generated by using the first key and the key information, and the key information attached to the encrypted contents. The contents decryption unit decrypts the encrypted contents by using the first key and the key information. The contents confirmation request unit instructs the communication apparatus to transmit or confirm the key information held by the communication apparatus, when the contents decryption unit decrypts the contents based on the second key firstly generated by using the first key.
