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Re:The ¬NED pin goes low on detection of a nuclear detonatio... by Daniel_Newby on Monday October 31, 2011 @11:32PM (#3180494)
Yes. More dense, lower power chips are more susceptible to radiation.

And anyway, what exactly does "redundancy" mean? If a rocket engine controller is triple redundant, how does that work? Are there three propellant valves in parallel, so each computer controls one-third of the thrust? Are they in series, so that failure of one computer disables the propulsion function? Is there a majority vote system, and is it electronic, electromechanical, or fluidic? Redundancy is not pixie dust that magically makes your system design better.

A sample Google interview question is to design the protocols to run a cluster of unreliable computers. Should there be a MIL-SPEC master computer? Should the cluster elect a master? Or several oligarch servers? Where does an outside agent submit a request, and what does it do if the request is not answered. Designing reliable systems is hard.

Re:The ¬NED pin goes low on detection of a nuclear detonatio... by nobody31 on Tuesday November 01, 2011 @12:07AM (#3180583)
Depends on the desired outcome.

For self destruct systems you probably want all three to agree before going bang - while for an emergency escape system you probably want any one of three to be sufficent to deplay.