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I'm an engineer with experience in applied cryptography, in particular in Smart Card systems.


Mar
22
revised Practical Attack on RSA
give juicy quotes of the wired article, and link to Batch NFS paper
Mar
22
revised Practical Attack on RSA
give juicy quotes of the wired article
Mar
22
revised How do you implement a cipher as one lookup table?
add missing end-of-TeX marker
Mar
22
revised Practical Attack on RSA
better choice of words
Mar
22
answered Purpose of expanding then shrinking in SHA-1
Mar
22
revised Purpose of expanding then shrinking in SHA-1
fix obvious typos
Mar
22
revised Practical Attack on RSA
polish
Mar
22
revised Practical Attack on RSA
Explain what the first answer implies. Polish.
Mar
22
answered Practical Attack on RSA
Mar
22
comment What prime lengths are used for RSA?
In order to get an answer to this, head there.
Mar
22
revised How do you implement a cipher as one lookup table?
Addition per comment
Mar
22
revised How do you implement a cipher as one lookup table?
explain notation
Mar
22
answered How do you implement a cipher as one lookup table?
Mar
21
comment Which algorithm can be performed by humans?
I added the pen-and-paper tag, explore that !
Mar
21
revised Which algorithm can be performed by humans?
add pen-and-paper tag
Mar
21
comment Are factorization algorithms parallelizable?
Yes in (MP)QS, and as far as I understand GNFS, the more time spent sieving with a given criteria to keep what's found, the more data there is for the later steps (grouping relations involving the same large factors to find better ones, then for matrix reduction step); and past some threshold, extra data does not help much. $\;$ But I'm talking of changing the sieving criteria (lowering the size of the factor base and large factor bounds), so that sieving becomes much harder (there are fewer reports), but there is less input to the matrix reduction step and it gets easier.
Mar
21
comment Are factorization algorithms parallelizable?
If one spends more time in the sieving step, one can significantly reduce the matrix reduction step (I do not know how far this can go). Also, there is work toward running the matrix reduction step in a partially distributed way, search parallel block Lanczos.
Mar
21
revised Coding of unsigned int to prevent guessing next ID
retag; edited tags
Mar
21
comment Coding of unsigned int to prevent guessing next ID
Indeed. Or any block cipher with a small block, as common in Format-Preserving Encryption. I have re-tagged the question accordingly. Following that tag will lead to many related questions with good answers.
Mar
20
revised Information-theoretic bound on leakage by timing measurement
Polish rationale