[SystemSafety] [External] Re: Post Office Horizon System

[Driscoll, Kevin]

PBL >> "Requirements specification is an unsolved engineering problem, and is likely to remain so for quite a while (if not for ever)."
ST > I would disagree, personally. Software requirements can be specified precisely, concisely, etc.
It depends on the definition of "requirements".  There are no end to stories of software that met its requirements, which was not fit for purpose.
One major problem is completeness (in breadth and depth).
I would lay down a bet that a substantial number of post mortems (particularly in security and safety-critical CPSs) would have the developers saying: "If we'd only known...".  Generally, these statements can't be completed by "... we would have written the software differently" without also including "we would have written the requirements differently".


-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.techfak.uni-bielefeld.de/pipermail/systemsafety/attachments/20210427/36b772f5/attachment-0001.html>