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From: aglew@ccvaxa.UUCP
Newsgroups: sci.crypt
Subject: Re: Declassifying some media.
Message-ID: <22700001@ccvaxa>
Date: Fri, 6-Nov-87 23:39:00 EST
Article-I.D.: ccvaxa.22700001
Posted: Fri Nov  6 23:39:00 1987
Date-Received: Wed, 11-Nov-87 06:33:11 EST
References: <12089@decwrl.DEC.COM>
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Nf-From: ccvaxa.UUCP!aglew    Nov  6 22:39:00 1987


..> Declassifying electronic media

Writing alnernating bands of zeroes and ones a few times might be a good start.
101010... 11001100... 1111000011110000....

Next, one would want to write a random bit pattern over the data you want
to declassify.

But even then you have to worry about jitter, about the analog bit patterns
not quite matching up with the original when overwriting. Plus effects that
might come from the tape running a bit slower/faster...