Martin Rosenau
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Why is the Keyspace of a Substitution Cipher not 2^26 but 2^88
5 votes

The key of your misunderstanding is the following sentence: Assuming the key length is 26 The conceptual mistake you made is that you forgot the unit: Does "26" mean "26 bits", "26 decimal digits"...

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Is one-time pad encryption vulnerable when near identical data is sent many times with different OTP?
2 votes

An alternative explanation: We could distinguish between two kinds of encryption methods: The first kind of encryption methods has the property that exactly one plain text can result in a certain ...

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If Kerckhoff's Principle holds, why do we need a cipher at all?
1 votes

I understand Kerckhoff's principle ... ... then why go through the trouble of creating a cipher in the first place? I think you misunderstood something: Kerckhoff's principle does not say that ...

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Bits of entropy needed to choose a random element from a list?
0 votes

My intuition says that I'd need to find $n$ such that $2^n$ is a multiple of list size, to ensure equal probability of selecting every item. First of all: The number of bits generated by some source ...

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Would asymmetric cryptography be feasible in World War II?
0 votes

Unfortunately, I cannot find the link, but I have read that some mathematician in the 18th or 19th century already had the idea that functions whose inverse function cannot be calculated with the ...

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