One indicator that a robust S-box is an ideal strict avalanche criterion value of 0.5. One method for applying the ideal strict avalanche criterion value is the selection of the precise irreducible polynomial and affine matrix. In this paper, we will discuss the robust S-boxes construction with the selected irreducible polynomial r(x) =x 8 + x 5 + x 3 + x 2 + 1 combined with the three selected affine matrixes i.e. t 1 , t 2 , and t 3 . Hence, the combination of selected irreducible polynomial

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... d affine matrixes results in S-box 1 , S-box 2 , and S-box 3 . The test of strict avalanche criterion shows that S-box 2 and S-box 3 produce the same value of 0.49951. Nonlinearity and bit independence criterion tests are also conducted to complete the S-box testing.This result shows S-box 2 and S-box 3 are the best S-boxes compared to S-box 1 and Sboxes from previous studies.