J
John Larkin
Guest
On Tue, 03 Feb 2009 18:04:32 -0600, John Fields
<jfields@austininstruments.com> wrote:
lots of formal theory. There's plenty of stuff on the web.
John
<jfields@austininstruments.com> wrote:
There is an extensive literature on LFSR's, dating back decades, withOn Mon, 02 Feb 2009 22:05:13 +0000, Nobody <nobody@nowhere.com> wrote:
On Mon, 02 Feb 2009 07:58:02 -0600, John Fields wrote:
Well, we could argue forever about what constitutes "[E]XOR-based", but
it's not an LFSR, and I thought it was clear that's what "nospam" was
referring to by "XOR-based PRNG".
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He was, and you're both wrong.
What you're saying, in effect, is that if an 8 cylinder ICE fitted with
a 7 cylinder ignition system was fitted with a system winch allowed all
8 cylinders to work it would no longer be an ICE, which is total
nonsense.
No, I'm saying that if you modify an LFSR so that its input is no longer
an N-input XOR of (some of) its outputs, it's no longer an LFSR.
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Well, I can't argue with that since it's the _feedback_ that's linear,
so I concede.
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I don't think that anone would contest that there exist *other* circuits
which will cycle through all 256 8-bit values, or at least don't have the
lock-up state.
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Your point being???
There are circuits which don't have the lockup state, but an LFSR isn't
one of them.
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And yet the LFSR lives within whatever it's called if it's EXOR feedback
based...
I suggest, since the non-linear portion of the counters' sequence is so
small, that they be dubbed Mostly Linear Feedback Shift Registers;
MLFSRs.
Got a problem with that?
JF
lots of formal theory. There's plenty of stuff on the web.
John