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From: sjl@amdahl.UUCP (Steve Langdon)
Newsgroups: net.micro.mac
Subject: Re: Medical Uses of a MAC
Message-ID: <3544@amdahl.UUCP>
Date: Thu, 14-Aug-86 04:42:26 EDT
Article-I.D.: amdahl.3544
Posted: Thu Aug 14 04:42:26 1986
Date-Received: Thu, 14-Aug-86 22:21:55 EDT
References: <3034@caip.RUTGERS.EDU> <266@dmsd.UUCP>
Reply-To: sjl@amdahl.UUCP (Steve Langdon)
Organization: Amdahl Corp, Advanced Systems Planning
Lines: 37
Keywords: Parity Mac Medical Risks
Summary: Parity does not make a system safe

In article <266@dmsd.UUCP> bass@dmsd.UUCP (John Bass) writes:

> Mac memory run's without parity and certain ESD events, AC line faults, and
> other powersupply problems can leave bits corrupted in memory without detection.
> Furthermore the error detection on Mac floppies is very poor.
> 
> Using computers without parity protection in critical medical service is a
> timebomb -- the resulting missinformation may kill someone.
> 
> I would say than any use of a mac to maintain charts, medication, or provide
> advisory AI services should be avoided ... use an IBM computer or some
> UNIX machine with parity memory and much better disk channel error detection.
> 
> Non-parity machines make nice toys, but I hope they stay out of medicine and
> other critical applications (fire, police, military, CIA, FBI, etc) where
> peoples lives are at stake.

[Sorry for the long quote, but it all seemed important]

I find myself in the rather unusual position of being forced to disagree with
John who's opinions I normally respect.  However, in this case I feel that he
is making a serious error in suggesting that parity and disk channel error
detection are the things that make a system suitable for "critical applications"
Good system design and proper checks and balances are much more important than
the difference between a small amount of error detection hardware and a medium
amount of error detection hardware.  I suspect that at least 2 orders of
magnitude more errors result from bad software design than the problems he
mentioned.

I believe that further discussion on this topic should move to mod.risks,
but I have not used a "Follow-up to" line to enforce this as others may
disagree.
-- 
Stephen J. Langdon                  ...!{ihnp4,cbosgd,hplabs,sun}!amdahl!sjl

[ The article above is not an official statement from any organization
  in the known universe. ]