Snoop-proof DSP: possible?

Clay wrote:

> On Oct 5, 12:10 pm, "steveu" <ste...@coppice.org> wrote:
> 
>>>I've seen where the circuit is potted in an explosive compound with an
>>>internal photo sensor and battery. Try to disolve away the potting
>>>compound and the circuit explodes - true you may try this in the dark,
>>>but you can put some other gottchas in the circuits that will likely
>>>get disturbed by working in the dark. And if the battery goes flat,
>>>the circuit forgets important data. True not 100% foolproof, but it
>>>does get pretty difficult to beat.
>>
>>Those things have an unpleasant safety record.
>>
>  
> True, but the items being protected are highly desirable and thus
> extreme protection methods being acceptable.

I've seen the physical self destruct mechanisms to protect sensitive 
stuff, too. However they included man in the loop. Somebody had to push 
red button.

There are also protected softwares, so if somebody tries to hack them, 
they kinda work, but randomly destroy files on the disk.

Vladimir Vassilevsky
DSP and Mixed Signal Design Consultant
http://www.abvolt.com