[SystemSafety] "Security Risk" and Probability

[Nick Tudor]

Have you read DO-356 (might be 355) which roughly equates DAL to EAL?
There is a table at para 2.6.2. To be clear, I don’t agree with it.

On Thu, 26 Oct 2017 at 08:15, Peter Bernard Ladkin <
ladkin at rvs.uni-bielefeld.de> wrote:

> Following on from my blog post yesterday about people's attempts to equate
> SILs, a safety
> requirement, with SLs, a security requirement, the question remains why
> one might want to try to do
> so. An evident motivation might be that both entail requirements on code
> quality. A higher SIL and a
> higher SL both require higher-quality code.
>
> I give a simple example in
>
> https://abnormaldistribution.org/index.php/2017/10/26/code-quality-for-safety-and-code-quality-for-security/
> of a design which has perfect code quality for safety properties and poor
> code quality for security
> properties. Code quality cannot be measured on one ordinal scale. It is
> multi-dimensional.
>
> That vitiates any argument through code quality for wanting to equate SILs
> with SLs.
>
> That code quality is parametrised by properties is obvious when you think
> about it. You write down
> the list of properties P you want the code to fulfil and maybe it fulfils
> them. That doesn't
> necessarily say anything about whether the code fulfils a completely
> different list of properties
> P'. But people do seem to forget it frequently.
>
> PBL
>
> Prof. Peter Bernard Ladkin, Bielefeld, Germany
> MoreInCommon
> Je suis Charlie
> Tel+msg +49 (0)521 880 7319  www.rvs-bi.de
>
>
>
>
>
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