Back-up systems.

Types of computing that can result in death:

• some kind of controller of something physical
• a system that produces data that people's exposure to something is based on
• a system that produces information used to decide if something or somewhere is safe

In the latter two cases, the calculation is usually done off-line, with time for reflection becfore action. What's needed is independent back-up calculations to corobborate the first one.

In the first case, controllers of physical systems, it's controller malfunction that is the danger. You must have either back-up controllers that monitor the primary and can detect malfunction and take over, or else security measures that physically prevent the system from doing anything dangerous even if the controller instructs it to do so.

In other words, if peoples' lives are really at stake, it's back-up systems you want to demand. Personally I'd ask for one in Perl and another in another language on a separate box.

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In reply to Re: Projects where people can die by punch_card_don
in thread Projects where people can die by cog

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