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5

In order for information-theoretic security to imply computational security, you need to require that the simulator run in time that is polynomial in the running time of the real adversary. This is the standard definition, specifically to avoid protocols such as you presented in your question. So, the answer is: If you allow the simulator to be unbounded ...


4

There is actually a field of study regarding provably secure block ciphers. The seminal paper was "How to construct pseudorandom permutations from pseudorandom functions" (1988) by Luby and Rackoff. Their paper used pseudorandom round functions in a Feistel construction, and proved that 4 rounds were sufficient to make the resulting block cipher a ...


1

I remember that BEAR and LION are two block ciphers are provably secure under the assumption that the primitives used (hash and stream cipher) are secure. This is the most "provable secure like" approach I can remember. A part of that, I think the securite of block ciphers are anaylized as the paper you have cited do. Checking the security against the ...


4

In symmetric cryptography it is hard to prove security properties on algorithm. Most of block ciphers relies on showing resistances to the current attacks (cf the paper you linked or any paper that introduce a new block cipher). As nobody can know what will be the next attack vector, it is not possible to be prepared against it. From The design of Rijndael ...



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