From: adacrypt on

Design details.

In theory at least the maximum message length is restricted only by
the maximum positive integer that the computer can store i.e.,

If ‘X’ is initialised at 1073741790 and the upper bound of N is 2 (X
+32) (for ASCII) then the maximum message-length is this upper bound
of N i.e. 2 (1073741790 +32) = 2147483644. (just less than the max.
positive integer that my 32-bit computer can store – 2147483647)

My claim for establishing the sequence of ‘N’s’ is validated by a
computer program that tests every possible combination of Key,
Plaintext and Modulus ‘N’ in any proposed range of N. Proof by any
other method is not to hand yet. The computer program in question is
named, “Make_Moduli_Program_Mark_0” and is to be seen and used by
readers in a free download from my website that is called,
http://www.scalarcryptography.co.uk

The five cipher versions that are to hand are written in the Ada-95
computer programming language, they have a high encryption/decryption
rate.

Appendix - A. – Mutual Database Technology.

Alice creates her encryption program to perfection complete with all
arrays of data that she normally needs. She immediately creates a
decryption program that decrypts her previous encryption work to
perfection using the same arrays. She can now decrypt her own
encryptions but so also can anyone else to whom she sends a copy of
her database. That person is Bob.

This requires a one-off secure delivery of her copy database by
whatever means is appropriate to the security level, it may even
require a delivery by a trusted live courier in extreme cases. No
other exchange of keying material is ever again needed in the life of
the secure loop. As long as the entities keep their databases secure
then they can enjoy theoretically unbreakable security of information
forevermore.
Alice exchanges scrambling parameters that keep the shared databases
in synchronism with Bob every so often. These scrambling parameters
may go as unsecured data along with the ciphertext. The ciphertext is
useless to anybody who intercepts it in transit because it merely
indexes the elements of the arrays in the databases of the entities
and without access to the databases it is totally worthless to any
adversary. There is nothing embedded within the ciphertext (as is the
case with modern encapsulation cryptography) that a cryptanalyst can
discover by mathematical means.
The ciphertext is a string of integers that have mathematically
dysfunctional periodicity – it has no regular scale and the space
between the integers is continually varying – this pre-empts all
inductive methodology by a cryptanalyst – hence the name “Scalable Key
Cryptography”.
Enjoy, - Austin O’Byrne – pseudonym “adacrypt”.

Appendix – B.
“A Handbook of Applied Cryptography” by A.Menezes, Paul Van Oorschot,
S Vanstone is a highly respected information reference and I quote
them as follows. The context is in relation to the generally unusable
One-Time-Pad cipher but is applicable also to all scalar ciphers which
includes this cipher type being called “Scalable Key Cryptography”
here by me.

Extract.
Quote: “ the One-Time Pad can be shown to be theoretically
unbreakable. That is, if a cryptanalyst has a cipher text string
encrypted using a random key string that has been used only once, the
cryptanalyst can do no better than guess at the plaintext being any
binary string of length ‘t’ i.e. (t-bit binary strings are equally
likely as plaintext). It has been proven that to realize an
unbreakable system requires a random key of the same length as the
message.
Unquote – Not well, this is not a one-Time pad cipher type.
NB. “used only once” means within that message on that occasion. It
does not mean ever before or ever again as one handbook wrongly
implies.

Comment.
One, or two random keys are optional in the cryptography being
described and the key lengths are studiously made equal to the message
length every time so as to satisfy this important caveat.

Finally, these ciphers are simple, transparent and robust. They can
claim theoretically unbreakable cryptographic strength. They are
written in the Ada-95 programming language, they have a high
encryption /decryption rate and are very efficient in terms of
ciphertext expanded volume. They are intended to be used by non-
specialist office staff who need only a minimal in what anybody could
call special training.

Comment.
I am not bound to using the standard denary values of the printable
subset of ASCII, I can revalue these at will but there is little
profit in doing this since I already have theoretically unbreakable
crypto strength and it becomes a case of gilding the lily to try to
add more unnecessary complexity. If I did decide to revalue the ASCII
printable subset however, then it’s a whole new ball game of finding
the new parameters that need to be calculated for finding the range of
N’s as moduli / keys. The latter is done just as before and is not
difficult.

By the same token, the methodology is extensible to any of the
language character sets of hexadecimal code-points in Unicode.

That’s it for now – A “Universal Model” is in the pipeline for posting
soon- adacrypt

-----------------------------------------