On weakly APN functions and 4-bit S-Boxes
نویسندگان
چکیده
S-Boxes are important security components of block ciphers. We provide theoretical results on necessary or sufficient criteria for an (invertible) 4-bit S-Box to be weakly APN. Thanks to a classification of 4-bit invertible S-Boxes achieved independently by De Canniére and Leander-Poschmann, we can strengthen our results with a computeraided proof. We also propose a class of 4-bit S-Boxes which are very strong from a security point of view.
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عنوان ژورنال:
- Finite Fields and Their Applications
دوره 18 شماره
صفحات -
تاریخ انتشار 2012