# [rc5] We may only need 5 years...

Eric Gindrup gindrup at okway.okstate.edu
Thu Oct 23 17:11:47 EDT 1997

```     Let's see 500 thousand IPs returned blocks to Bovine and only ~25
thousand were active at the end.  There's four doublings.  Machine
rates double every 18 months.  Easier clients will increase the viable
user population.  Yes, I think we can double the effort at that rate
for considerably longer.  Of course, this has all the hallmarks of
logistic growth.  Eventually, the user population will saturate, but
the stat I started off with indicates that we are far from there.
-- Eric Gindrup ! gindruP at okway.okstate.edu

Subject: Re: [rc5] We may only need 5 years...
Author:  <rc5 at llamas.net > at SMTP
Date:    10/23/97 4:10 PM

Eric Gindrup (gindrup at okway.okstate.edu), on 10/23/1997 4:51 PM, wrote
the following:

>     By eyeball at http://home.pacbell.net/cwax/bovineg.html, the Bovine
>     effort seems to double its number of completed keys count every 2.5
>     weeks.  Current keyrate is 5Gkps.
>     Let's say:
>     1.  We start RC5-64 right now.
>     2.  The doubling rate is constant for the duration I'm about to
>     compute.
>     3.  We have to exhaust all of the RC5-64 keyspace.
>
>     Let f(w) be the number of completed keys with w in weeks.  (The
>     following keeps about one significant digit.)
>     f'(0) = 5Gkps.  f(w+2.5) = 2*f(w).  These together mean f(w) =
>     1.4*2^(w/2.5).  To make this =2^64, w=160.
>
>     So, in 3 years, we could exhaust the keyspace.  We'd "probably" find
>     the key in about 18 months.  This is so terrible?
>             -- Eric Gindrup ! gindrup at okway.okstate.edu

And what exactly is the likelihood we could keep that doubling rate up
for that long?

Hah! Yeah right!

Seth Dillingham

-----------------------------------------
seth at snet.net
http://macrobyte.simplenet.com/sethspeak/
http://www.distributed-mac.net/
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