NODE 25efd8ddRe: Problems with certificates.
jamesd@echeque.comSun, 3 Mar 1996 23:13:43 +0800
At 08:35 AM 3/1/96 -0500, A. Padgett Peterson P.E. Information Security wrote:
>Today, each person generates their own PGP key. While it is unlikely that
>any two will match, it is likely that at some point some two will match
>(see matching birthdays in a bar - number is less than you would think).
If if we colonized every planet in the galaxy, and every planet had a
trillion people, and every single person on every planet generated a billion
keys a second for a billion billion years, not one pair would match, assuming
they were generated from truly random seeds.
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We have the right to defend ourselves | http://www.jim.com/jamesd/
and our property, because of the kind |
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derives from this right, not from the |
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NODE 4af69000Re: Problems with certificates.
"Perry E. Metzger" <perry@piermont.com>Sat, 2 Mar 1996 16:47:18 +0800
jamesd@echeque.com writes:
> At 08:35 AM 3/1/96 -0500, A. Padgett Peterson P.E. Information Security wrote
:
> >Today, each person generates their own PGP key. While it is unlikely that
> >any two will match, it is likely that at some point some two will match
> >(see matching birthdays in a bar - number is less than you would think).
>
> If if we colonized every planet in the galaxy, and every planet had a
> trillion people, and every single person on every planet generated a billion
> keys a second for a billion billion years, not one pair would match, assuming
> they were generated from truly random seeds.
Well, lets see. For a 1024 bit key, a birthday match is a 1 in 2^512
proposition, assuming that a key could be any random 1024 bit number.
Assuming 100 million planets:
100000000*(10^12)*(10^9)*60*60*24*365*(10^9)*(10^9)=
3153600000000000000000000000000000000000000000000000000
2^512=
134078079299425970995740249982058461274793658205923933777235614437217\
640300735469768018742981669034276900318581864860508537538828119465699\
46433649006084096
However, the density of prime numbers isn't so high as to make the
probability truly 1/2^512 -- indeed, I would guess it is much
lower. However, you may indeed be right.
None the less, one would hope that the software handled it gracefully
even if the impossible happened...
Perry