From: Ulf.Moeller@hamburg.netsurf.de (Ulf Moeller)
Date: Wed, 26 Jul 95 17:20:41 PDT
To: cypherpunks@toad.com
Subject: Re: NSA, Random Number Generation, Soviet Codes, Prohibition of
Message-ID: <m0sbGYf-000BHwC@ulf.mali.sub.org>
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In the book I mentioned there is a quotation of D. Kahn, The
Codebreakers, from 1967:

"Interestingly, some pads seem to be produced by typists and not by
machines. They show strike-overs and erasures - neither likely to be
made by machines. More significant are analsyses of the digits.
One such pad, for example, has seven times as many groups in which
digits in the 1-to-5 group alternate with digits in the 6-to-0
group, like 18293, as a purely random arrangement would have.
This suggests that the typist is striking alternately with her
left hand (which would type the 1-to-5 group on a Continental
machine) and her right hand (which would type the 6-to-0 group).
Again, instead of just half the groups beginning with a low number,
which would be expected in a random selection, three quarters of
them do, possibly because the typist is spacing with her right
hand, then starting a new group with her left. Fewer doubles and
triples appear than chance expects. Possible the girls, ordered
to type at random, sensed that some doublets and triplets would
occur in a random text but, misled by their conspiciousness,
minimized them. Despite these anomalies, however, the digits
still show far too little pattern to make cryptanalysis possible."

-- 
Ulf Mller * um@ulf.mali.sub.org * 3umoelle@informatik.uni-hamburg.de
PGP key fingerprint: B6 4F 97 28 8F C0 54 C3  A6 10 02 2F B9 31 78 14 
"When cryptography is outlawed, bayl bhgynjf jvyy unir cevinpl!"