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Probability conventions in cryptography

My understanding Please correct me if there is something wrong with my understanding. Without loss of generality, we first assume that the distinguisher $A$ is deterministic (since a probabilistic ...
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Probability conventions in cryptography

I completely understand your thoughts, I also had a similar question here. I will answer your question based on my understanding, I would like to hear any thoughts or disagreements, because I haven't ...
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Are Block Ciphers Pseudorandom functions?

Are Block Ciphers Pseudorandom functions? PseudoRandom Permutations (PRP, when keyed) are synonymous with block ciphers. This kind of implies that PRFs could be block cipher. Is this correct? block ...
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Are Block Ciphers Pseudorandom functions?

Pseudo-Random Generators -> generate sequences from bits which "look" like random -> a small sequence of really random bits. Stream ciphers Block ciphers, eg in Counter Mode Hash ...
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Why is using a truly random function in a fixed length encryption scheme not efficient?

Consider a truly random function $F:\{0,1\}^n\to\{0,1\}^n$. By a basic argument in combinatorics, writing down a description of $F$ takes $n2^n$ bits. Concretely, we often want $n\approx 128$ (...
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Is this pseudo random function any good and/or original?

The code in the question implements any one of the $2^{65\times64}\approx2^{(2^{12.02})}$ "affine" functions from $\{0,1\}^{64}$ to itself, that is functions with the property $$\forall u,v,...
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