| 摘要 |
PURPOSE:To attain the protection of a master key and error correction at the same time by applying error correction coding after the master key is scrambled and storing the result in a nonvolatile memory. CONSTITUTION:The master key for key distribution is inputted to a key input line 8 at the disconnection of an electric power supply, and after the key is scrambled at a control section 3, the result is subject to error correction coding and then stored in the nonvolatile memory 1. At the application of power again, the stored content is read from the memory 1, after after it is subject to error correction decoding at the control section 3, and descrambled and the master key is obtained. The master key obtained in this way is used to cipher and transmit the ciphering key. |
