Hi

I think that I seem to have successfully created and tested a very simple script which when run on a Windows VPS, serves as a building block for a True Random Number Generator. I am therefore wondering to myself, if it is this easy then what is the point of Pseudo Random Number Generators?

Here is the script.

#! /usr/bin/perl
use Time::HiRes qw(gettimeofday);

($seconds, $microseconds[0]) = gettimeofday;

for ($count = 1; $count <= 1000000; $count++)
  {
  }

($seconds, $microseconds[1]) = gettimeofday;

$difference = $microseconds[1] - $microseconds[0];

print "Content-type:text/html\n\n";
print "$difference";

[download]

Typical outputs:
46980
-953586
47168
67242
59319

As you can see from the above outputs, this script seems to work very well.

Would this script work as well on a dedicated server with a very fast CPU? Are timings on VPS servers particularly volatile? Would this script work as well on all Windows systems?

If I am creating an application which is critically dependent on a good quality TRNG, can anyone see any reason why it might be a mistake to depend on this script for the purpose?

Thank you very much.

Kind regards

Tim

In reply to TRNG Perl script query by tim.qfs

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