A Small Symmetric-key Crypto-Hardware
Original Publication Date: 2002-Jul-20
Included in the Prior Art Database: 2003-Jun-20
·Disclosed is a circuit for a symmetric cipher using a Feistel structure. In order to reduce the gate count, one S-box is implemented and is repeatedly used by switching the input data. When, n S-boxes are used, the right half of the data is divided into n words, and they are sequentially fed into the S-box. The permutation function is a linear transformation with an n-word input and an n-word output.