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Dec
4
comment Should we MAC-then-encrypt or encrypt-then-MAC?
"the MAC is not meant to preserve the integrity of the plaintext" would be just as good a reason to avoid MAC-then-encrypt too. $\;$
Dec
2
comment Creating serial key generator using ECDSA, how to get signature short enough?
If signature length is an issue, why are you public-key-encrypting the signatures? $\:$ A scheme with $\hspace{.24 in}$ shorter signatures "is the way to go for generating serial keys". $\;\;\;\;$
Dec
2
comment Creating serial key generator using ECDSA, how to get signature short enough?
Why are you specifying ECDSA? $\;$
Dec
1
comment Implementing a pseudo random function in practice
No, I'm saying that for most hash functions (even MD5), HMAC is believed to be a PRF. $\:$ I do not know whether something similar holds for CMAC, although there is another construction that's based on CMAC. $\:$ Every PRF with large output space is a MAC, but if there is a MAC then there is a MAC that is not a PRF. $\;\;$
Dec
1
comment Implementing a pseudo random function in practice
HMAC-SHA256 is "a function that gets used in practice for this this situation." $\;$
Nov
26
comment Computation indistinguishability questions
@Dramal : $\:$ $P\hspace{.02 in}(\hspace{.02 in}D\hspace{.02 in}(\hspace{.02 in}X_{\hspace{.02 in}n}\hspace{.02 in}))$ might make the "polynomial-time" constraint too strict. $\hspace{1.65 in}$
Nov
25
answered Computation indistinguishability questions
Nov
24
comment Efficient proof of knowledge using Wegman-Carter hash
No; I just mean that a similar analysis may work. $\;$
Nov
24
comment Efficient proof of knowledge using Wegman-Carter hash
I suspect that working with polynomials will have similar properties to working with integers. $\hspace{.94 in}$
Nov
21
comment Designing hash function in space-efficient identity based encryption
@poncho : $\:$ It would probably be important that the sampling of values $\hspace{2 in}$ with a Jacobi symbol of 1 be oblivious. $\;\;\;\;$
Nov
20
revised Cryptographic Operations and Security
improved grammar
Nov
19
answered Availability of a simple limited PRNG algorithm
Nov
19
comment Availability of a simple limited PRNG algorithm
Yes, there are at least 5 such PRNGs. $\;$
Nov
19
comment DHE key exchange. Is it really secure?
What "prefix" does Alice send to Bob? $\;$
Nov
19
revised Is it possible to determine a PGP public key from encrypted data?
inserted excerpts
Nov
18
reviewed Reviewed What does $\Pi$ represent in cryptography?
Nov
18
comment What does $\Pi$ represent in cryptography?
It can be "notation for the Encryption scheme in use", but isn't here. $\;$
Nov
18
revised How can I start the following crypto project?
fixed title's grammar
Nov
17
revised What does $\Pi$ represent in cryptography?
improved grammar
Nov
17
comment plaintext distribution ,perfect secrecy cryptosystem
However, "a perfect secrecy cryptosystem with specific plaintext probability distribution" would obviously be defined differently. $\;$