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From: newman@theory.tn.cornell.edu (Bill Newman)
Newsgroups: sci.electronics
Subject: Re: Library anti-theft walk-thru device...????
Message-ID: <1991May14.215441.1814@batcomputer.tn.cornell.edu>
Date: 14 May 91 21:54:41 GMT
References: <1991May14.155250.25003@cunixf.cc.columbia.edu> <1991May14.181148.15821@hubcap.clemson.edu> <1991May14.202632.3500@ux1.cso.uiuc.edu>
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In article <1991May14.202632.3500@ux1.cso.uiuc.edu> phil@ux1.cso.uiuc.edu (Phil Howard KA9WGN) writes:
>I see nothing wrong with describing how something works.
>
There are good arguments for this.

>We also have the technology to make things work in such a way that even
>someone who knows how it works can't break it anyway.  The problem is that
>we don't use this technology.
>
For the problem described in the title, this is not a good argument.
What kind of anti-theft device do you have in mind?
Powerful gamma ray sources on the books?  Perhaps
magnetic monopoles?  Any economical device I know of 
can be blocked.  And a thorough search of random customers 
is, well, a pain in the ass.  For computer security and cryptography, you can
make systems which are invulnerable even when your opponent knows
what you are doing.  For this kind of application, truly secure technology
seems out of reach.

  Bill Newman
  newman@theory.tn.cornell.edu