论文信息 - Understanding Two-Round Differentials in AES

Understanding Two-Round Differentials in AES

In this paper we study the probability of differentials and characteristics over 2 rounds of the AES with the objective to understand how the components of the AES round transformation interact in this respect. We extend and correct the analysis of the differential properties of the multiplicative inverse in GF(2n) given in [9]. We study the number of characteristics with EDP >0 whose probability adds up to the probability of a differential and derive formulas that allow to produce a close estimate of this number for any differential. We use the properties discovered in our study to explain the differentials with the maximum EDP values and describe the impact of the linear transformation in the AES S-box in this respect.

Vincent Rijmen | Joan Daemen | J. Daemen | V. Rijmen

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