Re: encryption with pi

From: Phil Carmody (thefatphil_demunged_at_yahoo.co.uk)
Date: 07/31/04 

Date: 31 Jul 2004 03:01:55 +0300

pubkeybreaker@aol.comstuff (Bob Silverman) writes:
> Sigh.

Agreed.
 
> I get tired of this. I am competent to judge.

Agreed.

> The proposed cipher is easily broken.

Agreed.

> Computing the
> n'th digit of Pi can be done in constant time
> (without computing prior values) by an algorithm of
> Simon Plouffe.

Borwein, Bailey and Plouffe claim the algorithm "scale[s]
nearly linearly with the order of the digit desired".
(That's from the abstract of their paper. The Bellard
improvements are simply a multiplicative constant, not
a change in Big-Oh)

> The algorithm is quite fast.
>
> Even if it were not constant time, generating 100
> million digits of Pi is TRIVIAL.

Agreed.

> I suggest searching the literature next time before
> shooting your mouth off. You do know how to do
> a Web search, don't you?

Funnily enough, about 75% of my bookmarks for BBP are now
dead links.

Phil 

-- 
1st bug in MS win2k source code found after 20 minutes: scanline.cpp
2nd and 3rd bug found after 10 more minutes: gethost.c
Both non-exploitable. (The 2nd/3rd ones might be, depending on the CRTL)

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