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Re: "S1" encryption system (was: this looked like it might be interesting)

In message <[email protected]>, Hal writes:
>I suppose the unstated implication is that this might be Skipjack.

I don't suppose anyone has access to Skipjack to verify or
refute this claim?

[...much intresting analisys deleted...]
>                                           In addition to the points
>mentioned it is curious that the G arrays are initialized with a list of
>256 values rather than taking advantage of the apparent regularities

It is fairly simple to cut & paste 10 values ~25 times, it is harder
to write and verify code to initilize the array.

More intresting is that Gx[i % 10] is faster then a stright index
on many systems (anything you could expect cache line conflicts or
cache capacity overfills on, and supports a modulis signifigantly
faster then the first few parts of the memory hierachy).

Also note that the code may have been written from a dissasembled
binary rather then a hardware spec.

>Hal Finney
>[email protected]