NODE 957de4f4Re: Seeds which depend on machine states
patrick@Verity.COM (Patrick Horgan)Fri, 22 Sep 95 08:23:07 PDT
>
> Miguel Diaz writes:
> > It is my suspicion that seeds which depend on machine
> > states(ie state of your computer at a specific instance of
> > time) would always be subject to scrutiny and de-cryption.
> > As long as the software used to encrypt is not self-modifying,
> > the machine state can (through careful manipulation involving
> > temperature, clocks, processes etc)always be replicated and
> > fixed to an acceptable degree.
>
> Try getting a human to type with the same timing, to microsecond
> precision, the same way twice.
>
That assumes that you have someway of measuring the timing to microsecond
precision. On most machines I've been on, if you get something time-
stamped, even if there is a microsecond portion of the timestamp it's
meaningless because it wasn't based on a timer with the required precision.
If a timer can only resolve milliseconds, the microseconds don't have any
meaning.
Patrick
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NODE 9d470eb8Re: Seeds which depend on machine states
"Perry E. Metzger" <perry@piermont.com>Sat, 23 Sep 95 08:43:53 PDT
Patrick Horgan writes:
> > Try getting a human to type with the same timing, to microsecond
> > precision, the same way twice.
> >
> That assumes that you have someway of measuring the timing to microsecond
> precision.
PCs have accurate microsecond timers.
Perry