> Any how do you know the code that does the checksum check 
> isn't corrupt?  I
> don't see any way you get around having to trust at least some code.

This is not (just) about trust. It is about matching a requirement,
instead of fighting it (choose what will be the least hassle).

When you have a knowing/flexible/communicative customer there are lots
of more sensible ways to get a hi-reliability system :)

Wouter van Ooijen

-- -------------------------------------------
Van Ooijen Technische Informatica: www.voti.nl
consultancy, development, PICmicro products
docent Hogeschool van Utrecht: www.voti.nl/hvu
 

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