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Oct
10
reviewed No Action Needed Generating a public key certificate with ECDSA params
Oct
10
comment Is it possible to demonstrate that md5(x) != x for any x?
One minor nit: the computation about a fixed point assumes a random function. MD5 isn't a random function, and might not behave as one (we don't know any specific way that it doesn't, at least, any way that appears relevant to the question), however that may be due more to our ignorance rather than the internals of MD5. However, it is an appropriate plausibility argument to say "there might be one, and there might not"
Oct
10
revised Serpent 256bit key wrong round keys
edited tags
Oct
10
revised Serpent Cipher 128bits (Example rounds on any plaintext/key)
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Oct
10
answered Block Cipher Modes
Oct
9
reviewed No Action Needed What is the sign bit for in Feige-Fiat-Shamir?
Oct
9
reviewed No Action Needed Do Export Restrictions Still Apply To The Key Length of RC4?
Oct
9
comment Do Export Restrictions Still Apply To The Key Length of RC4?
@CodesInChaos: unless you're exporting to North Korea, Syria, or an handful of other countries. If you want to export to those countries, it's a lot more than "fill out some paperwork"
Oct
9
comment How do I generate a number for a lottery and later proves its existence
@KentMuntheCaspersen: I missed where you said that
Oct
8
comment How costly is to find millions of large prime numbers for RSA?
@fgrieu: you're right; I was worried that if the step you take between sieved elements was too small, the discovered primes would be too close. However, if you're looking for primes for this purpose, you'd select a step of circa $2^{900}$ (say) for 1024 bit primes; the resulting primes would have plenty of spread. (To user153465): Doing this would mean that if someone found two primes, factoring the rest would be a lot easier; that's why fgrieu asked if that would be a problem
Oct
8
comment How costly is to find millions of large prime numbers for RSA?
@fgrieu: one requirement is that the product of two of those primes be hard to factor. The problem with those known algorithms is that they generate primes which are numerically close to each other, which means that their product may be easy to factor (say, via Fermat factorization)
Oct
8
comment How costly is to find millions of large prime numbers for RSA?
Mind if I ask about the problem you're solving? If you're trying to generate a large number of distinct RSA keys, well, there're actually faster approaches...
Oct
8
revised FEAL-4 Fk Function 4 Rounds
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Oct
7
comment Can adding nonces make challenge response authentications weaker?
@PlasmaHH: someone who tweaks a crypto design without knowing what they are doing is like someone who tweaks the shape of an airplane wing without knowing what they are doing -- what they do might be safe, but I wouldn't want to trust it...
Oct
6
revised How do I generate a number for a lottery and later proves its existence
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Oct
6
answered How do I generate a number for a lottery and later proves its existence
Oct
6
revised Differential Cryptanalysis of FEAL-4
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Oct
6
wiki created feal description
Oct
6
wiki created feal excerpt
Oct
6
revised FEAL-4 Wrong outputs of Round Functions
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