[SystemSafety] Correctness by Construction

[Peter Bernard Ladkin]

On 2020-07-13 21:55 , Dewi Daniels wrote:
> 
> In the context of “Correctness by Construction”, I would say that Correctness means “compliance with
> requirements”.

I deliberately avoided Michael's question as phrased. There is a phrase "Correct by Construction" or
CbyC. The subphrase "correct" is obviously not an applicative adjective. Consider the following
situation.

* suppose the client wants a system which protects against fires and explosions by initiating
countermeasures;
* suppose the developer has a specification which says "within 0.5 seconds, all flammable entities
should be ignited".

If we use your definition, it is possible to obtain a system which immediately sends the facility
sky-high, the complete opposite of what the client wants, but that is "correct". I think that is
anomalous.

I think it best to take "CbyC" as an atomic phrase.

PBL

Prof. Peter Bernard Ladkin, Bielefeld, Germany
Styelfy Bleibgsnd
Tel+msg +49 (0)521 880 7319  www.rvs-bi.de





-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 833 bytes
Desc: OpenPGP digital signature
URL: <https://lists.techfak.uni-bielefeld.de/pipermail/systemsafety/attachments/20200714/da7cce88/attachment-0001.sig>