Patent ID: 7886160

Claim:
An information processing apparatus for processing encrypted data input as a byte stream with dynamically changing decryption keys, the information processing apparatus comprising: a processor including an encrypted data receiving section configured to receive the encrypted data input as the byte stream, identify a range of the encrypted data that is encrypted using an identical key as a unit of decryption, extract information necessary for decryption from the byte stream, the information necessary for decryption including a decryption key or decryption key- related information for calculating the decryption key, generate encrypted data sets based on the extracted information necessary for decryption, segments of the encrypted data input as the byte stream, and one or more decryption key change points, and output the encrypted data sets in which the extracted information necessary for decryption is added to the segments of the encrypted data input as the byte stream; an encrypted data decrypting section configured to sequentially decrypt the encrypted data sets, based on the extracted information necessary for encryption included in the encrypted data sets, to generate plaintext data; and a plaintext processing section configured to process the generated plaintext data.