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17h
reviewed Close counting points not on elliptic curve
17h
reviewed Close Crypto Libraries with Pairing Based Functions for Academic and Educational Use?
17h
reviewed Leave Open What's algorithm encryption ?Twofish or AES
19h
comment To prove $r_2$ is a uniformly at random value in $Z_n$, where $r_2=r_1 . m$
By computation while they are at the server, you mean the RSA public or private operations? If so, well, what you're doing is known as RSA Blinding; it's a well known technique to allow someone to do the RSA operations without leaking what they're operating on. It's known to be safe.
19h
comment To prove $r_2$ is a uniformly at random value in $Z_n$, where $r_2=r_1 . m$
The answer to that would depend on what you mean by 'security'. You may find it helpful to write down exactly what you mean by that; what security properties are you expecting?
22h
comment To prove $r_2$ is a uniformly at random value in $Z_n$, where $r_2=r_1 . m$
@user153465: the answer to question 1 is "no"; if $m$ is an arbitrary value, consider the case that $m=0$; obviously in that case, $r_2$ is not a uniform random value. For the answer to question 1 to be "yes", we need to put restrictions on the distribution $m$ is chosen from (specifically, that probabilities that $m$ is a multiple of $p$, $q$ and $pq$ must be $1/p$, $1/q$ and $1/pq$)
1d
reviewed Close Protection of Elliptic Curve Implementations against side-channel attacks
1d
answered Does a stream cipher require a KDF when it's key is variable length?
2d
comment Does the transposition cipher have a network application?
@jake.toString: I suspect it'd be unlikely that anyone would write "we never use transposition ciphers in network applications" unless someone specifically asked.
2d
reviewed Close problem with “one time pad”
2d
comment problem with “one time pad”
possible duplicate of How does one attack a two-time pad (i.e. one time pad with key reuse)?
2d
reviewed Close Weak key schedule IDEA
2d
reviewed Leave Open I need to know number of encryption/decryption operations?
2d
comment Does the transposition cipher have a network application?
I'm not sure how to answer this other than saying that I've never seen a transposition cipher within a network security protocol, and I have a good deal of experience in that area. It's not clear to me why anyone would choose to use a transposition cipher as opposed to one we are confident is semantically secure.
Oct
15
awarded  Nice Answer
Oct
10
answered How do RSA and ElGamal key sizes compare?
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)
edited tags