[Cryptography] A software for combining text files to obtain high quality pseudo-random sequences in practice

[Ralf Senderek]

On Tue, 11 Jul 2017, Jerry Leichter wrote:

> However:  This reminds me of an old proposal - I don't recall where I saw it -
> for something of this sort as a much more secure version of a book code. 
> Take a high-resolution image as a source of bits; I think the original 
> suggested some NASA image of the moon.  A key is several starting points 
> and step sizes in a fixed linearization of the image.  Each starting 
> point and step size gives you a stream of bits.  XOR together and then 
> use the result as input to a stream cipher.

The original paper is by Ueli M. Maurer
"Conditionally-Perfect Secrecy and a Provably-Secure Randomized Cipher"

But there is no mention of the moon-image.

This reference is made in Schneiers criticism:

https://www.schneier.com/academic/paperfiles/paper-maurer-stream.pdf


     --ralf