| 摘要 |
A method of encryption of an ordered first set of bits that has a plurality of positions with each bit being in a respective one of the positions. The positions of the bits are rearranged in dependence on at least two encryption keys. Each position is identified by at least two identifiers in combination. The rearranging of the positions of the bits includes, for each position, the steps of determining the identifiers of a respective one of the positions using the encryption keys, and placing the bit in that one position in the corresponding position. The steps are performed by subjecting each bit in the first set to operation of an algorithm under the control of the encryption key. Specifically, each bit of the first set is placed sequentially in a respective position in a first array having N columns and N rows defining N<2> positions, each first identifier being indicative of a respective column, and each second identifier being indicative of a respective row. (Where N is greater than 1.) A corresponding method of decryption is also disclosed, in which the positions of the bits are rearranged in dependence on at least two decryption keys, corresponding respectively to the encryption keys, so that each bit is returned to its respective position in the first set before encryption. |
