John wrote:

> Once something is gone from RAM, it's really, really gone.  The circuit
> structure and the laws of thermodynamics ensure it.  No power on earth
> can do anything about that.

This is not =entirely= true.  A key stored in the same (non-swappable)
location for a long time will burn into the memory.  (I know that I am
reacting beside the point of your story, to which I agree.)

To understand this you have to know that semiconductor materials are
filled with ions (stored particles) and that some of those also reside
in the isolation layer between capacitor plates.  These ions tend to
be drawn towards the opposite charge.  They actually move a little over
time, especially if a system is hot -- this is normal degradation to
which all silicon chips are subject.

If the charge is consistently applied for a long time, as with long-term
key storage, the ions will actually move slightly, thus altering the
preferred state at switch-on ever so slightly.  When the memory is
switched on, this slight preference may be rounded to the bit of the
key (or its opposite) because it has to round 0.4999 down or 0.5001
up to form a 0 or 1 bit out of the analog state at switch-on.

A well-designed system would of course flip the key bits at regular
intervals if they are stored in non-swappable memory for long periods.
At least, that's what we have been doing for years  :)


Rick van Rein

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