[Cryptography] Terakey, An Encryption Method Whose Security Can Be Analyzed from First Principles

[Tom Mitchell]

On Mon, Jul 13, 2020 at 1:01 PM Jerry Leichter <leichter at lrw.com> wrote:
>
> Terakey(tm) is a cipher that offers confidentiality properties provable from first principles. It employs a shared secret key substantially larger than the anticipated volume of message traffic. Key bytes are extracted pseudo-randomly from the large key, using a message indicator as the seed....
>
> Gee, sounds like an old idea to use a high-resolution photo of the moon.  The way that was set up, the underlying random-looking database - in this case, the brightness values of the picture - didn't even have to be private.

With a large enough data set available and cacheable from anyplace in
the world this is interesting.
Full resolution images from the very large megapixel sample images
from Canon, Nikon, Hasselblad. Even
review sites like Ken Rockwell get interesting.

This NASA image might be more than big enough. ;-). 1.8 Billion pixels.
https://mars.nasa.gov/resources/curiositys-1-8-billion-pixel-panorama/?site=msl

It is easy to hide "dead" javascript code and data in web pages to
bootstrap encoding and decoding.

A problem with one time pads is the pad itself with multiple future
pages.  The Terakey(tm) idea has some
risk in this regard.  The shared key is evidence even if decoding the
message is unlikely.

Tricks like pseudo Captcha Verification that use a phone keypad like
array of images can direct someone to an error page fooNNNN where NNNN
is
a generated key to seed a PRNG and walk the image extracting bits.
Ray would know to click on the images of bears ignoring instructions.

All this is to say that key management is still key and hiding the key
safely involves something you know or can rediscover.
John 2.43 could be John Bolton's book and "HAVOC" the key. John 8:223
would have CHAOS as the key.   Kindle users?

A package solution for messages in transit is useful and an easier
problem than data storage.




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