Re: A new public key algorithm based on avalanche properties

From: Bill Unruh (unruh_at_string.physics.ubc.ca)
Date: 06/16/03 

Date: 16 Jun 2003 21:05:03 GMT

Colin Andrew Percival <cperciva@sfu.ca> writes:

]Tom St Denis <tomstdenis@iahu.ca> wrote:
]> Excuse the ignorance but as far as I know it is not generally true that
]> f o g == g o f
]> for random permutations f and g.

] True.

]> In fact the only case where that is
]> true is if f == g or f == g^-1 [e.g. f o g == I].

No, there are loads of permutations which communte. Eg for the permutations of 1234,
f=1<->2 and g=3<->4, they commute, Ie, if f is a permuation of a subset of the elements, and
g is a permuation of the rest of the elements, then f and g commute.

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