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visits member for 2 years, 8 months
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I'm an engineer with experience in applied cryptography, in particular in Smart Card systems.


Apr
12
wiki
Apr
12
wiki
Apr
12
asked Security of RSA for paranoids with padding?
Apr
12
revised Why are collision attacks important when talking about MAC schemes?
deleted 4 characters in body
Apr
12
comment Why are collision attacks important when talking about MAC schemes?
@user54609: 64-bit security against brute force key search is kinda ridiculous nowadays, but a 64-bit MAC is still very strong when the only way to check if it is right or wrong is try on the actual target and that takes 1 microsecond (that figure is unrealistically low even for a direct 10 Gbps Ethernet link): odds of success are worse than 1/500000 per year of continuous attack. Also, it is easy to detect such attacks.
Apr
12
revised Why are collision attacks important when talking about MAC schemes?
Polish
Apr
12
revised Why are collision attacks important when talking about MAC schemes?
Polish
Apr
12
revised Why are collision attacks important when talking about MAC schemes?
State that HMAC is affected, but some truncated MACs are not.
Apr
12
comment Why are collision attacks important when talking about MAC schemes?
@user54609: Yes, this attack works against HMAC with a hash using a 128-bit state, and e.g. allows a forgery of HMAC-MD5 in about $2^{64}$ queries. It does not contradict the fact that HMAC-MD5 remains practically unbroken as far as we know, when MD5 is not secure against collision, as supported by that security argument.
Apr
12
revised RSA: Letting $p$ and $q$ have different bit-size
Revise the stated limit of ECM vs GNFS to something unquestionable
Apr
12
comment Why are collision attacks important when talking about MAC schemes?
@DrLecter: That was not stated again in my last paragraph (now fixed). And it is worth noting.
Apr
12
revised Why are collision attacks important when talking about MAC schemes?
Detail "deterministic" and state that in the end, per comment
Apr
12
revised Why are collision attacks important when talking about MAC schemes?
Improve per comment
Apr
12
answered Why are collision attacks important when talking about MAC schemes?
Apr
12
comment Is there a simple zero knowledge proof of $x$ for $b=x^x\pmod p$?
Would someone care to compose an answer, preferably in zero knowledge for dummies style so that I can catch on?
Apr
12
revised Is there a simple zero knowledge proof of $x$ for $b=x^x\pmod p$?
TeXify the title
Apr
12
revised Turning a cipher into a hashing function
deleted 24 characters in body
Apr
12
revised Turning a cipher into a hashing function
Polish
Apr
12
revised Turning a cipher into a hashing function
edited body
Apr
12
revised Turning a cipher into a hashing function
Describe the Hirose construction