[RC5] Did the calculations again...

Daniel Quintiliani coredump0 at mercurylink.net
Tue Jan 6 16:41:55 EST 2004

Remember in October when we all did the calculations on when, based on 
Moore's Law, RC5-72 would reach 100% and I got "t = 17.20178906 years (17 
years, during the third month into the

I decided to do it again just now (based on yesterday's stats), since 
there have been new applicants and more processing power since October, 
and it would produce a more accurate result.

Our formula is:
t (in years) = ln(2^b/((k) ln(2^(1/1.5)))) / ln(2^(1/1.5))

k = Current Keys/s * 60 * 60 * 24 * 365.25
b = RC5-? (currently 72)

163536894738 Keys/s produces
k = 5.160831909 * 10^18

Our formula is:
t = ln(2^72/((5.160831909 * 10^18) ln(2^(1/1.5)))) / ln(2^(1/1.5))

That comes to 16.42712929 years (16 years, beginning of June) for all of 
the keys to be finished (from 399 days ago). That's a 9 month reduction 
 from a calculation three months ago! We may finish much sooner than we all 
think, especially since we usually find the key before we reach 100%.

Now I see what you mean about new participants. We should add that to the 
stats - when 100% will be reached if Moore's Law holds true during that 
time if no new participants join. (We currently only have those stats 
*without* calculating Moore's Law.) Check my math once more and I'll 
submit an enhancement request.


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