| 摘要 |
<p>According to an embodiment of the present invention, a safe cryptographic operation method of a cryptography system comprises the following steps: performing a cryptographic operation in a first-based cryptography function; performing an external operation for preventing a first subchannel by using a value operated in the first-based cryptographic function and first additional information; performing an operation for preventing a second subchannel by using a value calculated in the external operation process for preventing the first subchannel and second additional information; and performing a cryptographic operation in the first-based cryptographic function by using an operated value for preventing the second subchannel in a second cryptographic function. Accordingly, costs of a subchannel correspondence method for safe cryptographic communications can be significantly reduced.</p> |
