Method and device for protecting digital data by double re-encryption

摘要: A method and an apparatus ensuring protection of digital data are provided. In addition to re-encrypting the using unchangeable key, is double re-encrypted a changeable key. The key used first then used, or in another case, first, used. aspect embodiments, there case adopting software, hardware, software hardware combination. developed for video available. encryption/decryption performed region below kernel which cannot be handled by user ensure security program More concretely, with RTOS HAL device driver, i.e., filter disk driver network I/O manager. Either one two drivers, file system between them, may Further, both drivers