From: "Arthur J. O'Dwyer"
Subject: Re: the FBI and 1 time pads
Date: Sat, 30 Aug 2003 01:32:27 -0400 (EDT)
Organization: Carnegie Mellon, Pittsburgh, PA
References: <email@example.com> <3F4C55C1.114C@despam.autobahn.mb.ca>
NNTP-Posting-Date: 30 Aug 2003 05:32:28 GMT
On Fri, 29 Aug 2003, Benjamin Goldberg wrote:
> "Arthur J. O'Dwyer" wrote:
> > Neal Stephenson's _Cryptonomicon_ contains a brief anecdote somewhere
> > about how the Allies ended up having to change around their codes
> > sometime in the middle of WWII just because some little old lady got
> > lazy picking her bingo numbers. See, the Bletchley Park people had
> > hired a lot of women to pick letters out of bingo tumblers for their
> > one-time pads, and this woman eventually, subconsciously, realized that
> > the letters she was drawing "weren't random enough" -- you know,
> > sometimes she'd get two E's in a row, or three T's, and we all know that
> > really *random* letter arrangements won't repeat that often, and will
> > contain a lot of Q's and X's (because it's not just plain English; it's
> > random!). So she must have started putting a ball or two back into the
> > machine every so often,
> I think you mean, *not* putting the balls back into the machine.
> That is to say, drawing without replacement, instead of drawing with
Well, no; while the effect would be roughly the same, I think
it was more like
[little old lady voice]
F... W... T... J... S... I... A... T...
E... L... P... S... oh no, not another S!
I'll just toss that one back, and get a
*real* random letter this time. X, that's
better. X... G... Q... Y... D... E...
oh, there's that W again! Didn't that just
come up? I must not be mixing the balls
enough. Let's see, now... U... that's
...and every time a ball goes back into the bag
without being recorded (intentionally, of course),
that affects the distribution ever so slightly.