Questions tagged [matrix-multiplication]
Matrix multiplication indicates a row-by-column multiplication, where the entries in the Xth row of A are multiplied by the corresponding entries in the Yth column of B and then adding the results.
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Hill Cipher question
Recently, I was given three ciphers to crack for my cryptography class. At this point, I have guessed that one of them is likely a Hill cipher (probably 3x3, as that is the most complex we have done ...
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Constructing of 16x16 Involutory Binary Matrices of Branch Number 7
In the PDF “Algebraic Construction of 16×16 Binary Matrices of Branch Number 7 with One Fixed Point”, it was given that:
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Hill cipher cryptanalysis - known plaintext known key size
Hello I want to know how to go about this problem
I know the plaintext "abcdef" and the ciphertext. The key size is 2.
I really can't figure out how to find the key for decrypting and encrypting.
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hill cipher encryption way 1x3 plaintext matrix
Can someone help me with a Hill cipher?
When do I have to use:
1x3 plain text matrix (p1, p2, p3) * 3x3 key matrix
3x3 key matrix * 3x1 plain text matrix
Or they are both correct?
I tried to ...
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Matrix key exchange
Given is a square matrix $M$ over a field $F$, we have a key exchange with the following conditions:
Person $X$ sends a message to Person $Y$: $C_{1}=AM$, where $A$ is a randomly chosen square matrix....
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A substitution based on a matrix vector product
I choose at random an invertible square matrix A of size 128 in GF(2). I want to use this matrix as a substitution box. Is this a non linear transformation ?
I've seen that substitution boxes are ...
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What happen if a asymmetric crypto-system deals with only one key
Assume there is a crypto algorithm that deals with matrices to encrypt and decrypt. Regardless of the specification of such algorithm, what if the algorithm assumes that two parties can securely agree ...
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How to multiply a matrix of bits with another?
For example, assume I have two 4x4 matrices of bits:
1 1 1 1 1 1 1 0
0 0 0 0 0 1 1 1
1 0 0 1 1 0 1 1
0 1 1 1 1 0 1 0
I want to apply ...
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