From: Jim Gillogly <jim@acm.org>
Date: Wed, 12 Jul 95 09:03:15 PDT
To: cypherpunks@toad.com
Subject: Rosenberg/VENONA: two time pads [Re: QED_jak]
In-Reply-To: <9507121445.AA10531@snark.imsi.com>
Message-ID: <199507121601.JAA20564@mycroft.rand.org>
MIME-Version: 1.0
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> "Perry E. Metzger" <perry@imsi.com> writes:

> The reports claimed the spys were using one time pads in some flawed
> manner, but did not explain very well what the problem was. Does
> anyone out there know?

The AP story by Rita Beamish says:

   The Venona program translated 2,200 telegrams intercepted mostly from
   1942 to 1945.  They were double encoded with a complex numerical system
   that used a different random pattern for each message, officials said.
   The code would have been impossible to crack had not the volume of
   traffic resulted in the Soviets sloppily repeating some of the
   patterns, said Kahn.

The "repeating some of the patterns" means to me "two time pad".  Lots of
work in general, but doable, unlike the one time pad.

	Jim Gillogly
	Mersday, 19 Afterlithe S.R. 1995, 16:00