Mission Critical Definition and Compliance

Mission Critical Definition and Compliance

[John J. Cupak Jr.]

I have been asked to locate the *official* definition of "Mission
Critical" software, together with the process for defining which
language comply with it.

I "know" that Ada is a Mission Critical (approved) language, but Java
and C++ are not. Why? Who decides? Where is this published?

Inquiring minds want to really know!

Any pointers to the place(s) where this information resides would be
greatly appreciated. Thanks!

-- 
----------------------------------------------------------------
-                   John J. Cupak Jr, CCP                      -
- Raytheon Electronic Systems: Software Engineering Laboratory -
- tel: 508-858-1222     email (work): jcj@swl.msd.ray.com      -
- fax: 508-858-4336     email (home): jcupak@aol.com           -
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Re: Mission Critical Definition and Compliance

[Markus Kuhn]

John J. Cupak Jr. wrote:
> I have been asked to locate the *official* definition of "Mission
> Critical" software, together with the process for defining which
> language comply with it.
> 
> I "know" that Ada is a Mission Critical (approved) language, but Java
> and C++ are not. Why? Who decides? Where is this published?

IEC 1508 recommends the use of a safe subset of Ada
for SIL4 components. SPARK is probably the language of choice
for the design of such systems.

C is only allowed for SIL1 and SIL2 components, C++ is not at all
recommended for any safety critical software.

http://www.mod1ndrl.demon.co.uk/SSP84/Chapter9.html
http://www.mod1ndrl.demon.co.uk/SSP83/Chapter9.html

Don't know about Java, but the JavaSoft License conditions
prohibited the use of Java in any safety critical applications
the last time I saw them.

Markus

-- 
Markus G. Kuhn, Security Group, Computer Lab, Cambridge University, UK
email: mkuhn at acm.org,  home page: <http://www.cl.cam.ac.uk/~mgk25/>

Re: Mission Critical Definition and Compliance

[Ed Falis]

John J. Cupak Jr. wrote in article <34D0F22A.41C67EA6@swl.msd.ray.com>...

>I have been asked to locate the *official* definition of "Mission
>Critical" software, together with the process for defining which
>language comply with it.
>
>I "know" that Ada is a Mission Critical (approved) language, but Java
>and C++ are not. Why? Who decides? Where is this published?
>


I don't think there is such a thing as an official definition of a term so
broad as to be jargon.  Common usage seems to converge on software whose
"correct" operation is essential to an organization achieving its aims.
Lots of room for splitting hairs and counting angels there.  Sort of like
mission statements.

(not really being sarcastic, here, but I couldn't resist saying something)

- Ed Falis
Aonix

Re: Mission Critical Definition and Compliance

[Steve Doiel]

If my memory serves me correctly, I first heard the term "Mission Critical"
when IBM
announced the release of the first version of there CSet for OS/2.  It is
ammusing to
see Microsoft using the same terminology on occasion ;-)

SteveD

John J. Cupak Jr. wrote in message <34D0F22A.41C67EA6@swl.msd.ray.com>...
>I have been asked to locate the *official* definition of "Mission
>Critical" software, together with the process for defining which
>language comply with it.
>
>I "know" that Ada is a Mission Critical (approved) language, but Java
>and C++ are not. Why? Who decides? Where is this published?
>
>Inquiring minds want to really know!
>
>Any pointers to the place(s) where this information resides would be
>greatly appreciated. Thanks!
>
>--
>----------------------------------------------------------------
>-                   John J. Cupak Jr, CCP                      -
>- Raytheon Electronic Systems: Software Engineering Laboratory -
>- tel: 508-858-1222     email (work): jcj@swl.msd.ray.com      -
>- fax: 508-858-4336     email (home): jcupak@aol.com           -
>----------------------------------------------------------------

Re: Mission Critical Definition and Compliance

[JP Thornley]

In article: <34D0F22A.41C67EA6@swl.msd.ray.com>  "John J. Cupak Jr." 
<jcj@swl.msd.ray.com> writes:
> I have been asked to locate the *official* definition of "Mission
> Critical" software, together with the process for defining which
> language comply with it.
> 

I would use the term to distinguish it from safety-critical (with which 
some people confuse it).

My informal defitions are something like:-

Safety-critical code is any code whose incorrect operation creates the 
risk of an accident leading to death or serious injury.

Mission-critical code is any code whose incorrect operation places a 
mission at risk, but doesn't create any significant risk of an accident.

So if mission-critical code goes wrong then the plane has to turn back, 
but can be expected to return safely, if safety-critical code goes wrong 
then the plane might not get back at all.

HTH

Phil

-- 
------------------------------------------------------------------------
| JP Thornley    EMail jpt@diphi.demon.co.uk                           |
|                      phil.thornley@acm.org                           |
------------------------------------------------------------------------

Re: Mission Critical Definition and Compliance

[Marin David Condic]

John J. Cupak Jr. wrote:
> 
> I have been asked to locate the *official* definition of "Mission
> Critical" software, together with the process for defining which
> language comply with it.
> 
> I "know" that Ada is a Mission Critical (approved) language, but Java
> and C++ are not. Why? Who decides? Where is this published?
> 
> Inquiring minds want to really know!
> 
> Any pointers to the place(s) where this information resides would be
> greatly appreciated. Thanks!
> 

This is not going to be very helpful, but it is the truth:

One of the things you will discover on this quest is that the answer to
the question "What is mission-critical" is going to depend on who you
ask.

Lieutenant Colonel John A. (Drew) Hamilton, Jr., US Army, delivered a
talk at the last TriAda conference that dealt in part with this
question. I think this is available from the AdaIC somewhere - try this:
http://sw-eng.falls-church.va.us/AdaIC/
Look in the past issues of their newsletters.

Since the DoD dropped the Ada mandate, we have been left with much
confusion and uncertainty about what is going to be O.K. and what is
not. Even the people involved don't really know where its going to go.

Good luck with the quest. 

MDC
-- 
Marin David Condic

    "Languages don't kill people. Programmers do!"