In message <[EMAIL PROTECTED]>, John Cochran writes:
> [snip...]
>
>> If I generate true random bits it takes 3 timestamps to get one
>> bit of randomness:
>>
>> T1: Time of event 1
>> T2: Time of event 2
>> T3: Time of event 3
>>
>> if (T2 - T1 > T3 - T2)
>> return 0;
>> else if (T2 - T1 < T3 - T2)
>> return 1;
>> else
>> try again.
>>
>> In my rather crude setup it produces about 5 bits per second [3].
>
>It seems to me that if you get about 15 events per second, then you
>should be able to produce about 7 to 8 random bits per second instead
>of only 5. What you're looking for is the difference (greater or less)
>between events. Because of this your T3 value can be considered the T1
>value for the next random bit you generate.
No it cannot. If you did that then the probability would skew from
bit to bit. If the (t3-t2) was large bit N == 1 and the probability
of bit N+1 == 0 is > .5 then.
--
Poul-Henning Kamp | UNIX since Zilog Zeus 3.20
[EMAIL PROTECTED] | TCP/IP since RFC 956
FreeBSD coreteam member | BSD since 4.3-tahoe
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