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Apr
7
comment Is it possible to determine or estimate the period for Blum-Micali PRG?
The premise seems faulty. Cycles can occur even if there is no fixed point. So, focusing on fixed points seems mis-placed, if you really care about cycles. But, as I explain in my answer, worrying about short cycles is also mis-placed concern.
Apr
7
answered Is it possible to determine or estimate the period for Blum-Micali PRG?
Apr
6
reviewed Reject suggested edit on Wrong Test Vector for HKDF with HMAC-SHA256
Apr
6
comment Wrong Test Vector for HKDF with HMAC-SHA256
This question appears to be off-topic because it is about software development (try StackOverflow).
Apr
5
awarded  Favorite Question
Apr
5
comment Should we MAC-then-encrypt or encrypt-then-MAC?
I edited the answer to more clearly express the point Josef was trying to make. Personally, I think the answer is fine (I upvoted it).
Apr
5
revised Random oracle model proofs and programmability
Improve the title & question a bit.
Apr
5
reviewed Reject suggested edit on Random oracle model proofs and programmability
Apr
4
revised Should we MAC-then-encrypt or encrypt-then-MAC?
added 448 characters in body
Apr
3
answered Key-dependent encryption in TAHOE-LAFS
Apr
3
comment What are the exact steps to decryption in International data Encryption Algorithm (IDEA)?
What research have you done? Have you read the IDEA spec? Have you read reference code? We expect you to do some significant research on your own before asking here.
Apr
3
comment Key-dependent encryption in TAHOE-LAFS
What is ENC, specifically? How is it instantiated?
Apr
2
answered How do I create a short signature? (e.g. less than 100 bytes)
Apr
2
comment Combining multiple symmetric encryption algorithms - implications?
@StephenTouset, oh, right, thank you! Boy that was a dumb thing to write. :-) I appreciate the comment.
Apr
2
revised Combining multiple symmetric encryption algorithms - implications?
Address a typo spotted by Stephen Touset.
Mar
31
answered Operation sequence authentication shared storage
Mar
31
comment Can a commutative block cipher be indistinguishable from a random permutation, for fixed key?
@fgrieu, yes, maybe posting a separate question would be best. When you do, can you spell out how we choose a random set of permutations with the commutativity property? Is that notion uniquely defined?
Mar
30
comment HKDF vs TLS PRF. Which of the one is better?
Better, in what sense? More secure, in what sense? For what purposes? Under what threat model? This question is too vague as it stands; I suggest you edit it to make it more specific.
Mar
30
comment Is it possible to find an attack that can reduce the key space of the Hill cipher with $d*d$ key matrix to $26^d$
You tagged your question with hill-cipher. Look through the other questions with the same tag, and you'll find plenty of attacks on the Hill cipher that reduce the key space far further. There are also standard attacks described all over the Internet. Next time, please do more research before posting. We expect you to make a serious effort on your own to answer your own question before asking here.
Mar
29
comment Is Porticor's “homomorphic” key encryption something that can really be done or is it just marketing hype?
Can you edit your answer to provide a summary of the contents of those documents and their implications for the answer to the question that was asked here? As it stands, the main content of your answer is the links, but on this site we tend not to like link-only answers very much, because links may rot or disappear.