[SystemSafety] What do we know about software reliability?

[hugues.bonnin at free.fr]

> Suppose something bad happens and people are hurt. What are the
> consequences? Do I go to jail, or is
> it nothing to do with me?

then the police will enquire if the "something bad" is due to:
- the clients that did go out of your usage specifications
- your usage specifications which were not sufficiently retrictive, regarding the normal and forseeable usage that the clients did
In this "usage", I include all the "forseeable" conditions of it. Which can potentially change with time.

The key point for me is the "forseeability", behind which is all the "accepted human limit" of the system engineering. The state of the art observation (potentially expressed in standards, norms) by your teams will be examined; it is a part of this forseeability, to which is added an "acceptability" notion (of risks and their mitigation means), applicated to your engineering, for example.

And clearly, the "zero failure ten years" will enter in this forseeability evaluation. Your advocates will just need some mathematical backgrounds to defend it. 

Finally, this statistics could contradict the state of the art of your engineering. In this case, either it is defendable to show the limits of the state of the art, and it will evolve after this judgment, or it is not, and it means, in this court at least, that there was something to do more during your engineering.


I hope that this reasoning helps...

regards,

Hugues 

----- Mail original -----
> De: "Peter Bernard Ladkin" <ladkin at causalis.com>
> À: "Robert P. Schaefer" <rps at mit.edu>
> Cc: systemsafety at lists.techfak.uni-bielefeld.de
> Envoyé: Mardi 15 Septembre 2020 22:58:46
> Objet: Re: [SystemSafety] What do we know about software reliability?
> 
> 
> 
> On 2020-09-15 20:02 , Robert P. Schaefer wrote:
> > that the new use is similar to past use within bounds set by you,
> > and the users are experienced and trained within bounds set by you
> 
> Great. Everything's up to me.
> 
> Suppose something bad happens and people are hurt. What are the
> consequences? Do I go to jail, or is
> it nothing to do with me?
> 
> PBL
> 
> Prof. Peter Bernard Ladkin, Bielefeld, Germany
> Styelfy Bleibgsnd
> Tel+msg +49 (0)521 880 7319  www.rvs-bi.de
> 
> 
> 
> 
> 
> 
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