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Jan
7
comment Why use 256-bit symmetric encryption in TLS when 2048-bit RSA doesn't even offer 128-bit strength?
Belief that "key entropy" acts like some kind of sci-fi shield strength that is incrementally consumed by cryptanalytic attacks, is unsubstantiated. It is a common reflex to go for longer keys as if it granted some sort of "security margin", but in fact attacks don't work that way. In the case of AES and the only known non-trivial attacks (which are related-key attacks so not an immediate worry), 256-bit keys turn out to be weaker than 128-bit keys, not stronger. The only case where longer keys are actually "stronger" is against brute force, for which 128-bit keys are already strong enough.
Dec
30
awarded  Revival
Dec
28
awarded  Enlightened
Dec
28
awarded  Nice Answer
Dec
26
awarded  Enlightened
Dec
26
awarded  Nice Answer
Dec
25
awarded  Good Answer
Dec
21
comment How is user authentication sent in a public wifi? Radius/802.1x/EAP etc
Some routers intercept the first outgoing HTTP connection and replace it with the router "login page"; but the client system will not send that request unless it has first resolved the IP address of the target server, so DNS has to go through.
Dec
20
awarded  Good Answer
Dec
19
revised Does the entire AES encrypted dataset have to be present to be 'cracked'?
added 25 characters in body
Dec
19
comment Does the entire AES encrypted dataset have to be present to be 'cracked'?
If the PRNG output is in some way predictable by attackers, then the security properties achieved by the "splitting" are reduced, possibly lost completely -- at which point you still have an AES-encrypted string, which should resist until the end of times (unless the encryption key can be guessed, e.g. it was generated with the same flawed PRNG; or the library that uses AES to "encrypt a string" turns out to do something stupid, e.g. CBC with a fixed IV for all strings).
Dec
19
awarded  Enlightened
Dec
19
awarded  Nice Answer
Dec
19
answered Does the entire AES encrypted dataset have to be present to be 'cracked'?
Dec
18
comment Are there implementations of password hashing algorithms for major frameworks that utilizes specialized hardware like GPUs/FPGAs?
There are proposals that support heavy parallelism, and you can always turn a CPU-hard (not memory-hard) function parallel by defining h'(p,s) = h(p,s) XOR h(p,s+1) XOR h(p,s+2)... (p = password, s = salt). Whether this brings the defender on par with the attacker remains to be seen: it depends on whether the defender has GPU (e.g. on his server). There is also all the debate about buying vs running costs (e.g. GPU tend to use a lot of energy, and some people argue that in the long run, power consumption is what matters for the average attack cost).
Dec
17
awarded  tls
Dec
17
awarded  tls
Dec
17
awarded  tls
Dec
16
awarded  Announcer
Dec
15
comment SHA1 - S/MIME and CRL validity after deprecation?
The job of the TSA is to keep its clock accurate, in the same way as the job of a CA is to make sure that it does not issue a certificate to the wrong person. No cryptographic algorithm ever creates trust; it just moves it around.