> Beyond that, how difficult is it for someone to, as Alan just suggested,
> remove the epoxy on the chip and erase the code protct bits to then
> download all the hex code?  Sure, they've got to disasseble it and
> reverse engineer it, but can they easily get at it?  Is removing the epoxy
> to expose the die a real possibility or just a very difficult to achieve
> project or outright myth?

A document I read this week, which I hoped would give me some
pointers about protecting an encryption algorithm stopped me in my
tracks. The authors cited the example of back-engineering an 80386
in 2 weeks. Even if exotic chip-reading equipment costs millions, you
don't have to buy it, only get access to it, and there are plenty of
facilities
around that do have the necessary tools. It seems if you're protecting
anything short of missile launch codes, you just have to take your chances
by deterring the majority of hackers. If your code does get broken, you
still have copyright/registration/patent laws to help in the long term. Not
much consolation if you're up against a fly-by-night sweat-shop but you
gotta have something to help you sleep at night

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