An IC card chip performs payment processing in response to item purchase in accordance with a command generated and encrypted by a secure application module. The IC card chip decrypts the encrypted command, and reads information corresponding to the command. The IC card chip appropriately encrypts the read information in accordance with key information managed together with the secure application module, and sends the encrypted information to the secure application module via a cellular telephone or the like. The secure application module generates a command for controlling the IC card chip of the cellular telephone in accordance with a request from a content server. The secure application module appropriately encrypts the generated command in accordance with the key information managed together with the IC card chip, and supplies the encrypted command to the IC card chip. The IC card chip operates in accordance with the supplied command.