Re: RNG in a Smart Card

Ben Laurie (ben@algroup.co.uk)
Fri, 31 Jul 1998 16:42:32 +0100

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Just thought I'd explain the 50/60 ms thing seen in PC timings for those
who don't know (note that the 40ms Enzo reported didn't actually occur
in the data).

50/60 ms is a consequence of the standard PC tick rate, which is the
maximum divisor for the clock, yielding 18.2 ticks/second, or very close
to 55 ms. Clearly something else is also rounding to 10 ms intervals,
thus yielding a neat mixture of 50 and 60 ms intervals, in more-or-less
equal proportions (in fact 50 ms should be just a teeny bit more
common).

Cheers,

Ben.

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