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How can I generate an random number in protected mode?

>On 2001-12-10 11:22:55, Iwabee wrote:
>How can I generate an random number in protected mode?

Without a source of radioactivity you can't

You can get pseudo-random numbers though...
The typical approach is to have an algorithm that takes
the current time as a seed and does some wacky computation
with it.

Random number generation has had alot of research.
A quick search on google should turn up a bunch of different
methods and downloadable implementations.

>On 2001-12-10 11:22:55, Iwabee wrote:
>How can I generate an random number in protected mode?

Try this: Make a cycling calculation of the
square root of two and then make a 'device'
entery for your OS that returns the curent
location in the computation. Store the value
somewhere in a file and start again at that
place when you restart your computer.
Another way is to take a value, square it,
take the 3 center digits, and use that value,
then square the number formed of those 3 digits,
square that, take the 3 center digits and keep
repeating.

>On 2001-12-10 17:24:38, Chase wrote:
>>On 2001-12-10 11:22:55, Iwabee wrote:
>>How can I generate an random number in protected mode?
>
>Without a source of radioactivity you can't
>

Actually, the newer Intel chipsets all have
hardware RNG based on measurement of thermal
fluctuations in the BIOS die. see
http://www.intel.com/design/security/rng/rngppr.htm
for details.

Other random number systems have been available
as bus cards for years. Most of those use either
a variation on the thermal fluctuations system,
or use a 'noise generator' of some kind (for
example, a wire or semiconductor chip that has a unpredictably variable resistance; this results
in a truly random variation that can be detected
by a built-in ohmmeter).

However, to date only a small minority of systems
have these. The usual suggestion is to use a
conventional PRNG as your main algorithm, and to
use the RNG for providing it seed if there is
one; otherwise, use a traditional seed-generation
method such as sampling the current time in
seconds and XORing it to the time of the previous
run.