Re: NSA and crypto

"Ed Weir \(ComCast\)" <Anon@xxxxxxxx> wrote in


So, David - where are your test results? I really would like to see

-- Ed.

My crystal ball is still in the shop after I tried to use it to see
when it would get out. Now it can only see backward in time...

If I thought it would help I would show some to you but I don't think
you really care. The tests are very simple for many files all I did
was to run a compression then a decompression to see if file matches.
I then take the test file and do a decompression first followed by
a compression to see it it gets back to the same file.

The first tests for something like arb255 was every one byte file
as a starting file then files with lots of zeros or ones then common
test files. And then other files that have come up know and then.

Many of the tests where run with varible register sizes. I use for default
the full 64 bit state registers why use 32 or less. I also changed size
with a mask to see the change with less then 64 bits you can change with
very little mods to code. IN every case this last verision of arb255
worked like I expected it to.

arb255 is made up of many seqments that where tested as I developed
it. For example the compressor actually only works with strings. So
many thousands of strings tested for the I/O byte to string conversions
that take place. There are many ways to bijective handle the space of
all byte files to strings. I ended up using what I call the stability
method of file I/O for the compression there is a porblem that a very
short file can decompress to a very large file if the file is all ones
or zeros. So I store the file a pusedo random way so that the string
of all ones or zeros does not cause a massive decompression. Oh the
massive decompression is still there it just that your more apt to
accidently try to decompress a file of all zeroes or ones or some
other highly structured file then the files that would casue massive
decompression. To find such a file for the decompression porblem
Just take any repeated string of any byte. Make millions of bytes
long. These will compress to a very short file where some bits in
the compressed file can stand for thousands of bits in the decompressed
file. But to the eyes the compressed file will still look random.
And with only a few bits changed in the front of file it will
decompress to a totally different file much shorter in length.
airthmetic compression is really neat.

Look many get confuesed I am saying the code works on all files
you can think of them either as compressed or uncompressed. And like
any other general file compressor. Most files in the space of all
files are random and that in general compressing random files actully
makes them longer. Bijective compression or decompression is nothing
more than rearangeing files with the hope that highly useful redunant
files get susituted with shorter files. I am not going to violate
the counting therom so please don't go there.

David A. Scott
My Crypto code old version
My Compression code
**TO EMAIL ME drop the roman "five" **
Disclaimer:I am in no way responsible for any of the statements
made in the above text. For all I know I might be drugged.
As a famous person once said "any cryptograhic
system is only as strong as its weakest link"


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