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

On 10 Feb, 12:33, clark <c...@xxxxxxxxxxx> wrote:
I'll try this again...

On 6 Feb 2007 12:28:49 -0800, j...@xxxxxxxx wrote:

<snip discordant stuff>

Well ok now i had it *PLEASE RUN MY CIPHER* with a one byte key or two
byte password/key and you will notice one thing about the stream *IT
HAS SAME ENTROPY THAT A 256 BYTE KEY*

So you are saying (and doing a lot of hand-waving and shouting) that
using a one byte password/key gives the same entropy as using a 256
byte password/key.

No i never said a that the a ONE byte key has same entropy as a 256
byte key.
I said that a *STREAM* generated from a ONE byte key have same
properties and entropy as a *STREAM* generated from a 256 byte key.

Thus the algorithm will not now the *ORIGINAL* length of key, because
it is expanded into a 256 byte block "THAT IS KEYDEPENDENT" and there
is no trouble doing this since 256! is a lot bigger 2^256 or 2^8
whateever keylength you chose that is smaller than 256!.

The *FACT* that keys of different lengths can create same properties
and entropy of *STREAM* is due to use of permutations(shuffles) and
*KEYEXPANDING*

I think you very well understand the difference of these concepts.


As long as you meant a maximum entropy of 8 bits then that is true.

But it looks like you are deriving entropy from a false source.

Well the key will never have more than 8 bit entropy.....

Either way, it seems you do not understand the principles of entropy,
or what someone means when they say they have, say, 80 bits of
entropy.

I know very well......

You don't understand entropy, do you?

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*

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

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

Blah blah blah

.

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