From: "Cynthia H. Brown" <cynthb@sonetis.com>
Date: Wed, 9 Apr 1997 14:43:59 -0700 (PDT)
To: Lucky Green <shamrock@netcom.com>
Subject: Re: Black box attacks (was Re: Crypto-Dongel)
In-Reply-To: <3.0.32.19970409134223.007296b8@netcom13.netcom.com>
Message-ID: <Pine.BSD/.3.91.970409170243.266C-100000@mrburns.iosphere.net>
MIME-Version: 1.0
Content-Type: text/plain


On Wed, 9 Apr 1997, Lucky Green wrote:

> At 12:35 PM 4/9/97 -0400, Cynthia H. Brown wrote:
> >If you're trying to destroy a standard IC, why don't you just hook up the
> >power and ground pins to a 120V AC outlet? 
> 
> You are unlikely to have AC in a system by the time the tamper detector
> senses an intrusion. Similar problems apply to arcs and anything based on
> discharging a large capacitor.

True, if you haven't installed a circuit in advance with some sort of
switch or circuit breaker to kick in when the PC's cover is opened (in
your absence), or the Big Red Button beside your PC is pushed (in your
presence).  Assuming you're dealing with a PCMCIA card, it would be easy
to rig up an alternate "reader" to fry the card as soon as it's plugged
in. 

All of this has been done before - most high-security crypto devices have
built-in zeroisation / tamper response. 

And no, I'm not sufficiently paranoid to have this on _my_ home PC.

Cynthia

===============================================================
		   Cynthia H. Brown, P.Eng.
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