Re: Key entropy, stream entropy, block entropy, block population entropy AKA uniique stream length

On 10 Feb, 14:50, clark <c...@xxxxxxxxxxx> wrote:
On 10 Feb 2007 04:11:42 -0800, j...@xxxxxxxx wrote:



On 10 Feb, 12:33, clark <c...@xxxxxxxxxxx> wrote:
<snip>

You don't understand entropy, do you?

And this argument help you in what way, it looks like handwaving but
it could also a desperat call for help.

Yes i do in a binary with the given length x the entropy is 2^x, in
plaintext english the number of possible unique states a binarystring
of that *SPECIFIC LENGTH*

You should though try to decode the meaning of *SPECIFIC LENGTH* and
try to logically deduce the connection to *KEYEXPANSION* and
*SHUFFLES*

If the key expansion or shuffles are generated from an algorithm only
and do not include input from a hardware RNG or cryptographically
sound CSPRNG like /dev/random or from another entropic source like
random mouse movements or the outcome of rolling dice... things like
that, then what is there to decode?

I will give you an *EXAMPE* now suppose there is a generator(PRNG) for
one *STRING "STREAM"* of the length 256!*2^2048.

Suppose there is a very clever *DUDE* that realise he just can reach
different offsets within that string even with passwords of different
length, that would make some people very *NERVOUS*.

Because they do not now what the *STREAM* contains and they never
will. Because the offsets is very far between eachother. In fact so
far they realise they have no option then to bruteforce to find the
offsets in the *STREAM*

Now this *DUDE* not only make the key totally scaleable, also the
actual algorithm is totally scaleable *AND NOW REAL CRYPTOGRAPHERS*
get *REALLY NERVOUS*
Because they realise they can not distinguish the different sizes of
the *ALGORITHM* from eachother.

At this point they pretty much give up every hope, and *REALLY*
*REALLY* hope that this just all will blow away without anyone taking
notice of the *DUDE*.

They even send some of their *PETS* who do not understand the subject
to try riddicule hime and scare him away.

And that is just all fine.

Jonas Thörnvall

there would be no way to actually generate the complete string

You cannot derive entropy where none exists.

I do not hold high hopes that it will enlighten you, the least.

But, then again, you appear to be the one who needs to be enlightened.

How are your high hopes doing with that issue?

I mean... you use the word constantly... but you appear to not
understand what it means, particularly as regards crypto.

Blah blah blah

Well... yes... that is all you are doing. Why don't you say something
knowledgable about entropy?

Really. Instead of speaking about it using terms you made up and have
no basis in reality, why not try to actually apply the real meaning to
what you are saying.

Then you would quickly see that maybe your high hopes and dreams and
shmeems and fleems about entropy may indeed be true in some other
parallel universe, but not here on planet earth.


.

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