Nth digit of PI

[Steven D. Arnold]

At 05:36 PM 6/16/2000 +0000, Robert Israel wrote:
>In article <394a5ed7.83928743 at 10.1.1.28>,
>Tim Dixon <tdixon.no at spam.fwi.com> wrote:
> >>
> >>This is a collosally bad idea, IMO.
>
> >Just for curiosity, why?
>
>Because the real key is the number of the digit that you start at, and
>that's pitifully small by cryptographic standards.  The time to generate
>the n'th digit is not much less than the time to generate all the digits
>up to the n'th, given that you have lots of memory available.  So the
>cryptanalyst with a computer somewhat bigger than yours could try all
>the keys you could be using.

Perhaps we could specify a key; the key would be a sequence which we would 
find in pi.  The next bit in pi would be the start of our one-time 
pad.  For example, the key might be the first ten words in today's London 
Times.

This would likely give us a very large n and yet it is still an easy 
requirement to transmit.

Course, this idea too might have holes the size of a Mack truck -- I liked 
the previous idea too until you shot it down. ;-)


--
Steven D. Arnold           Que quiero sera         stevena at neosynapse.net
"If you have  built castles in the air, your work  need not be lost; that
is where they should be.  Now put the foundations under them!" -- Thoreau