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bio website github.com/CodesInChaos
location Frankfurt, Germany
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visits member for 2 years, 9 months
seen 13 hours ago

Mar
5
comment Long-term data protection, storage of old encrypted traffic and quantum cryptocalipse
@Thomas A big quantum speedup for travelling salesman would be a far bigger revelation than even breaking 4096 bit RSA, since QCs are not believed to solve NP complete problems quickly. D-Wave can solve one specific optimization problem which is closely related to their physical structure. They don't entangle many qubits at the same time, can't run shor, it's dubious that they even offer a quantum speedup for their one favourite optimization problem. In short, D-Wave is useless and not representative of real quantum computers.
Mar
5
comment Long-term data protection, storage of old encrypted traffic and quantum cryptocalipse
@Thomas Just because there are no large quantum computers yet,(don't remember the precise current state of the art, but it's around 5 qubits factoring huge semi-primes like 15) doesn't mean that there won't be such QCs twenty years from now. If you want long term confidentiality QCs resistance should be a consideration.
Mar
5
comment Prime factors of non-random keys
Another related article There’s no need to panic over factorable keys–just mind your Ps and Qs. @fgrieu That paper is pretty high on my list of "dumbest paper titles".
Mar
5
revised elgamal-encryption wiki description
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Mar
5
revised elgamal-encryption wiki excerpt
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Mar
3
comment Three-way hash collision
You get a $2^l$ way collision with cost $l \cdot 2^{64}$. So you get a 16-way collision with cost $2^{66} = 4 \cdot 2^{64}$ not just an eight-way collision.
Mar
3
comment Machine Learning with Encryption
Related questions: Any practical uses of machine learning for cryptography? and Cryptography based upon neural networks
Mar
3
comment Machine Learning with Encryption
You might be able to throw machine learning at side-channel or meta data. But that's a bit beyond crypto per-se.
Mar
3
comment Machine Learning with Encryption
The crypto techniques somewhat related to machine learning that I know of are 1) using SAT solvers as part of cryptoanalysis 2) Learning with error problems in lattice based crypto
Mar
3
comment Check the validity of a rsa key pair with only the public key?
Blind RSA signatures might have some issues if the modulus has a small factors since padded signatures/blinding factors might share factors with the modulus.
Mar
3
comment Derive both MAC and AES keys from same PBKDF2?
@fgrieu I mainly base it on performance, i.e. on the issue describes in that answer. I also think that being able to specify an arbitrary info string is nice.
Feb
28
revised How to calculate the time it'll take to crack RSA or DH?
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Feb
28
revised Solving a discrete logarithm using GDlog
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Feb
28
revised Why Elliptic curve cryptography are not popular in practice
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Feb
28
revised Does ElGamal Encryption create a different key for each block sent?
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Feb
28
revised Generating a valid signature on El-Gamal without knowing the private key
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Feb
28
revised Z*p Generator (Cyclic Group) in java
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Feb
28
revised ElGamal signature without calculating the inverse
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Feb
28
revised ElGamal signature - exploiting fallacious implementation
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Feb
28
revised Mapping between subgroups and the integers
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