How can we find the minimum number of differentially active s-boxes in a block cipher (actually a Feistel network with several input cells) in a truncated characteristic form? In a recursive algorithm when we get to the situation that there are binary cases, I don't know what to do? For example when I get a xor of two nonzero characteristics, there are two cases nonzero and zero, How can recursive algorithm be applied in this state?

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    $\begingroup$ Explain more, by example. Your second paragraph is incomprehensible to me. $\endgroup$
    – kodlu
    Commented Mar 4, 2018 at 19:29

1 Answer 1


There many methods to find the number of active sboxes such as:

  1. search algorithm , you input different scenarios , it is time-expensive process.

  2. Matsui algorithm. code

  3. Mixed integer linear programming.

    I recommend you to try MIxed integer linear programming


Differential and Linear Cryptanalysis using Mixed-Integer Linear Programming

Automatic Security Evaluation of Block Ciphers with S-bP Structures against Related-key Differential Attacks

New Impossible Differential Search Tool from Design and Cryptanalysis Aspects


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