Re: Non-Scalar Cryptography - The Emporor is stark naked.

On Mon, 12 May 2008 14:00:20 -0700 (PDT), austin.obyrne@xxxxxxxxxxxxxx
wrote:

Key management,

In all the computerised ciphers that I refer to as having written,
there is no key transport per se - Alice and Bob have exactly the same
databases of shared information - established at the outset by
unsecured ordinary mail - in my cipher this a keystring (array) of
14000- laboriously keyed-in alphanumeric characters
So we can assume that any attacker has access to the same database of
characters since it is transmitted unsecured.

. Once this set of keys is established, Alice and Bob liaise by Alice
sending scrambling parameters for the keys array to Bob for each new
message - this ensures the 'once only' bit of OTP rigour.........(1)
So the database is not actually the key as such, the actual key is the
particular permutation of the database that you are using - your
"scrambling parameters". How many bits are there in these scrambling
parameters? How easy would it be for an attacker, who has access to a
copy of the database, to brute force the scrambling parameters?

How secure is the scrambling algorithm against an attacker who has
access to the database, the plaintext and the cyphertext - can such an
attacker recover the scrambling parameters?

as well as solving the traditional ket [key?] transport problem ......(2)
How are you transporting the "scrambling parameters"? Since your
database is unsecured, and hence public, then the scrambling
parameters *are* the key. The attacker already knows the database.
If the attacker also learns, or can guess, the scrambling parameters
then the cypher is presumably broken. This is not looking much like
OTP to me.


It simply happens as a convenience in the programming that each
plaintext is enciphered one at a time and the corresponding element of
ciphertext is stored in a growing array of ciphertext such that the
eventual string of ciphertext is numerically equal to the length of
the plain text message - this ensures that piece of OTP rigour....(3)
You may want to allow for padding of messages. If the attacker knows
that the message is either "yes" or "no" and that the cyphertext is
the same length as the plaintext then the length of the cyphertext
leaks information.

rossum


Finally, and most importantly the randomness of the ciphertext is
argued axiomatically as being of equal uncertainty between the
separate elements of the ciphertext string => equal uncertainty means
equal probably => means randomness by definition. The argument for
randomness based on equal uncertainty is reinforced by the
alphanumeric character of the ciphertext string => there are no
mechanical methods, lexical ( Babbage / Kasiski style of attack). no
arithmetical methods ( the presence of keys like %, *. ^ $ that are
not arithmetical data pers se), and lastly numerical analysis is foile
d by the same reasoning ie the alphanurmic string of ciphertext is bad
data to each style of attack => the upshot of this reasone randomness.

The cipher can handle a message of any length between 1 and 14000
characters - any longer thatn this measn two blocks as separate pieces
- 14000 characters ios about 5 A4 pages.

Because of the newness of this cipher one has to keep an open mind on
what the industry authorities may think of it and of course be ready
accept whatever they say.

It would be great help if anybody would help out with the Beta -
Testing of the cipher - just running the program and noting anything
that you think needs changing - contact me at :

austin.obyrne@xxxxxxxxxxxxx

Thanks - adacrypt.

.

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