| 摘要 |
A method of providing security in a computer system includes producing an initial block of data from a respective address of a memory location. An updated block of data may be calculated for each round of a plurality of rounds in a substitution-permutation network. This may include mixing an input block through a substitution layer including a plurality of substitution boxes, and a linear transformation layer including a permutation, to produce the updated block, before or after which respectively the input block or updated block may be mixed with a round key. The input block may be the initial block for the first round, and the updated block for an immediately preceding round for each round thereafter. A block of ciphertext may be produced with a key composed of the updated block for the last round, and the block of ciphertext may be written at the memory location. |
