peter green wrote:
>> That property is hardly unique to LFSRs.  Since pseudo-random number
>> generators are deterministic algorithms run on deterministic machines
>> with finite memory, they ALL repeat.
> indeed however with a large enough internal state, the right algorithm and a
> sufficiantly random initial seed value predicting the next output from the
> previous outputs can be made practically impossible.

I always come at things from a cryptographic point of view.  In short,
"No, you cannot."  :)

> it really depends, if its just got to look random to the untrained eye then
> you'll probablly get away with 8 bits of state but if it has to defeat
> trained cryptographers you will need FAR more.

To trained cryptographers, you need true random and/or true
unpredictable state.

--Michael

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