Questions tagged [cryptography]
Questions on the mathematics behind cryptography, cryptanalysis, encryption and decryption, and the making and breaking of codes and ciphers.
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Finding a primitive root of a prime number
How would you find a primitive root of a prime number such as 761? How do you pick the primitive roots to test? Randomly?
Thanks
user27617
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Mathematically, why was the Enigma machine so hard to crack?
Mathematically, why was the Enigma machine so hard to crack?
In laymen terms, what was it exactly that made cracking the Enigma machine such a formidable task? Everything I have seen about the Enigma ...
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Would a proof to the Riemann Hypothesis affect security?
If a solution was found to the Riemann Hypothesis, would it have any effect on the security of things such as RSA protection? Would it make cracking large numbers easier?
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Why are very large prime numbers important in cryptography?
Firstly, you guys are awesome, and I learn quite a bit just from reading the questions of others.
Secondly, a friend asked me recently why large primes are important for data security, and I was ...
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What is an elliptic curve, and how are they used in cryptography?
I hear a lot about Elliptic Curve Cryptography these days, but I'm still not quite sure what they are or how they relate to crypto...
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Proving the Riemann Hypothesis and Impact on Cryptography
I was talking with a friend last night, and she raised the topic of the Clay Millennium Prize problems. I mentioned that my "favorite" problem is the Riemann Hypothesis; I explained what it posits ...
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Is there a way to find the log of very large numbers?
I should like to evaluate $\log_2{256!}$ or other large numbers to find 'bits' of information. For example, I'd need three bits of information to represent the seven days of the week since $\lceil \...
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RSA in plain English
I'm a computer science student, I'm not a mathematician, I don't know anything about number or group theory.
I'm looking at RSA, and I want to understand it.
I know what Fermats's little theorem and ...
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Homomorphic Compression
Can there be an algorithm such that, given plaintext data P,Q, and compression function e,
Such that if we treat P and Q as a number (a series of bits):
$$\begin{eqnarray*}e(P + Q)& =& e(P) +...
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Why does (1/3) mod 3016 = 2011?
So I am taking a class where we are working on a cryptography section. Basically, the course says that:
$$\frac 1 3 \mod(3016) = 2011$$
or when run through Python - modified with SciPi:
$$\frac 1 3 \,...
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good books on Abstract Algebra and Cryptography for self-study
I want to self-study some abstract algebra and cryptography during the summer, so what are some of books that are suitable for self-study? I have very limited background in algebra and none in ...
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Book recomendation for Elliptic-curve cryptography
I have already taken a course on Cryptography, The course focused mainly on the public-key cryptography based on the algebraic structure of elliptic curves over finite fields. Now, I would like to ...
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RSA: How Euler's Theorem is used?
I'm trying to understand the working of RSA algorithm. I am getting confused in the decryption part.
I'm assuming
$$n = pq$$
$$m = \phi(n) = (p - 1)(q - 1)$$
E is the encryption key $\gcd(\phi(n), ...
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How to break XOR cipher with repeating key?
I need to crack a stream cipher with a repeating key.
The length of the key is definitely 16. Each key can be any of the characters numbered 32-126 in ASCII.
The algorithm goes like this:
Let's say ...
user8689
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Does the Riemann hypothesis guarantee that integer factorization is difficult?
In an exchange of comments at Is there any mathematical conjecture that is successfully applied in the real world in spite of being yet unproven?, user R.J. Etienne claims that
RH guarantees that ...
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