I was under the impression that a more common notation was 'U,D,F,B,L,R for 90° clockwise turns, 'U²,D²,F²,B²,L²,R²' for 90° turns, and either 'U',D',F',B',L',R'' ('prime') or 'U^-1,D^-1,F^-1,B^-1,L^-1,R^-1' for 90° anti-clockwise. The obvious advantage of this system is that U' or U^-1 imply the inverse of U.

I would be inclined to agree with you to the security of the cryptosystem. Istr that a 2x2 cube has only ~10⁷ permutations, which strikes me as a rather small number compared to those people throw around when talking about PGP (but then, i am not a cryptologist). The number of permutations increases exponentially with cube size, so if you a use a bigger one, this may cease to be a problem.

It would be really cool if you could use the resulting cryptosystem using nothing but a Rubik's cube, some paper, and a lot of free time (à la '<cite>Pontifex</cite>'), but maybe that's a little optimistic.....

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Some interesting cube-related links from my bookmarks:

• How to solve the Rubik's cube
• Data structures for the Rubik's cube.
• Lecture notes on the mathematics of the Rubik's cube
• Solving Rubik's cube using the 'bestfast' search algorithm and 'profile' tables

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In reply to RE: RE: Rubix by kilinrax
in thread Rubix by japhy

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