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I SHALL DEVOUR YOUR HEART AND FEAST ON YOUR SOUL (so don't bug me).


Apr
22
comment Password strength with grouping of characters
@Ian the question is about adding three dots to a 20-character password, not replacing three characters in a 23-char password with dots. We assume the attacker knows all about the extra dots; he still has 20 non-dot characters to guess. The underlying question is whether these known dots induce extra structural weakness due to some postulated weird interaction with the hash function computation; that, is, weakness beyond the fact that the attacker knows 3 of the 23 password characters, and has "only" 20 more to guess.
Apr
22
answered Password strength with grouping of characters
Apr
22
awarded  Nice Answer
Apr
22
awarded  Nice Answer
Apr
21
answered If TLS 1.2 is considered unbreakable, why do the NSA and other agencies invest in supercomputers?
Apr
21
comment Which is better for server-to-server-communication: IPSec or TLS?
"Layers" are ill-defined. For instance, if you use a TLS-based VPN, then the TLS must be both above layer 4 and below layer 3, a logical impossibility. Trying to map all network activity into the rigid "layer" terminology is bound to be restrictive and spread confusion. As for combining two encryption systems to obtain "maximum security", it is called cascading and is not really recommended (cascading surely increases usage cost, but it "increases" security only insofar as one of the cascaded protocols is broken, and it would be smarter not to use a broken protocol at all).
Apr
21
comment Securing a prediction about a future event
Length does not provide entropy. It merely provides room for entropy. The "80 bits" value is the traditional limit of computational feasibility, though the relentless increase in computational power of computers should warrant, at some time, a new traditional limit (cryptographers being in love with powers of 2, they now often talk about "128 bits" as that absolute limit).
Apr
9
awarded  Nice Answer
Apr
6
awarded  Nice Answer
Apr
1
awarded  md5
Mar
30
awarded  Nice Answer
Mar
25
awarded  Revival
Mar
23
awarded  Guru
Mar
21
awarded  Enlightened
Mar
21
awarded  Nice Answer
Mar
16
awarded  Revival
Mar
16
comment What certificates are needed for multi-level subdomains?
As I wrote, what RFC 2818 states and what browsers do are different things. Browsers are a lot more restrictive. RFC 6125 is closer to what actually happens in practice. (The server species does not matter here, only the certificate contents and the Web browser.)
Mar
13
comment Begin of Certificate/ End of Certificate dash “-----”
Note that for a long time, the use of encapsulation boundary for certificates was not standardized anywhere; it was best defined as "whatever OpenSSL does and can process". Not including exactly five dashes incurs the risk of being rejected by OpenSSL or one of the other implementations that can understand that format (including the certificate support code in Windows).
Mar
12
comment rainbow table for AES 256 CBC knowing IV, cipher text and plain text
Well, if they use both the same key and IV, and begin with the same sequence of bytes, then the encrypted versions will also be identical, up to the first 16-byte block where the plaintexts diverge. From the outside, you will be able to see on which block this occurs (the encrypted blocks will diverge at that point), so you indirectly gain some information on the unknown message (you learn that you actually know it up to the diverging block). That's about it.
Mar
12
awarded  Necromancer