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seen Dec 5 '13 at 21:15

May
5
comment Is there any strong enough pen-and-paper or mind cipher?
RC4 doesn't have good reputation, though I don't know if it's completely broken yet. According to answer, Solitaire seems to be a weaker version of RC4.
May
5
comment What's the difference between AES and earlier block ciphers?
Is there any difference from user's point of view?
May
4
comment Is there a secure cryptosystem that can be performed mentally?
Is RC4 really safe today? And if no, is Solitaire even less secure?
May
4
comment What is the most secure hand cipher?
@DavidCary only if it's used properly. Otherwise it quickly mutates to the most unsecure.
May
4
comment What is the most secure hand cipher?
Is it really strong, or is it a toy cipher with no real strength?
May
4
comment Why is elliptic curve cryptography not widely used, compared to RSA?
Another advantage of RSA: public key operations (encryption/sig verification) are still faster than for ECC with same strength.
Apr
26
comment What data is saved in RSA private key?
That works :) Somehow I haven't got a notification or haven't noticed it. Why is all this data saved? Is it not enough to save just p, q, e and probably d? What are first and second exponent used for? Is there any integrity check performed to verify that these variables are consistent?
Apr
20
comment Does key authentication in SSH protect from MitM?
Let's speak only about public key cryptography, as it's the one attacked by MitM.
Apr
17
comment implications of SSH server key compromission when authenticating users against a public key
@PaĆ­loEbermann see below
Apr
17
comment Does key authentication in SSH protect from MitM?
Does someone else share the opinios of user1451340?
Apr
16
comment implications of SSH server key compromission when authenticating users against a public key
Does it change something if the mitmer knows client's public key and thus can decrypt the session key? Can server connection be downgraded to use RSA? Do typical SSH configuration explicitely require DH?
Apr
16
comment Does key authentication in SSH protect from MitM?
But maybe you want to move this question to security.stackexchange.com. - Why? crypto.stackexchange.com/questions/3706/…
Apr
16
comment implications of SSH server key compromission when authenticating users against a public key
@CodesInChaos can the mitmer use RSA for client connection and DH for server connection so that he gets the same session key for both connections?
Apr
4
comment Can one have an authentic, but repudiable, message without a previously shared secret?
But you don't know whom the key belongs. But if you say you use signed DH, all will be fine.
Apr
4
comment Can one have an authentic, but repudiable, message without a previously shared secret?
DH provides no authentication.
Apr
4
comment Does a trace of SSL packets provide a proof of data authenticity?
SSL also provides integrity. Is this mechanism symmetric too?
Mar
27
comment Even passwords are vulnerable to hash collision attacks?
Interesting. Can you provide real numbers for some hash functions?
Mar
25
comment Even passwords are vulnerable to hash collision attacks?
Duadratic security is more that enough :) Even MD4 which is completely unresistant to collisions is resistant to first and second preimages - at least, no successful attacks are known.
Mar
24
comment Even passwords are vulnerable to hash collision attacks?
I assumed first preimage is something that works with selected hash function and is faster than general purpose attacks like bruteforce or rainbow.
Mar
23
comment Secure modulus length for Diffie-Hellman
Yes, but computing capabilities have grown a litte since then.