Re: [Model-t] Dependable, secure, flexible and extensible

Carsten Bormann <cabo@tzi.org> Wed, 05 February 2020 20:18 UTC

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From: Carsten Bormann <cabo@tzi.org>
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To: Robin Wilton <wilton@isoc.org>
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Subject: Re: [Model-t] Dependable, secure, flexible and extensible
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On 2020-02-05, at 18:33, Robin Wilton <wilton@isoc.org> wrote:
> 
>  "Dependable, flexible and extensible" might legitimately be considered as “availability” pre-requisites,

It’s the other way around, availability is a component of dependability.
(A system may be available, but not doing the right thing, which makes it less dependable.)

Flexible (capable of doing things that were not expected by the designer) and extensible (enabling designing in things that were previously not expected by the designer) are certainly on the “do the right thing” side as well.

Dependability may require accountability, including third-party verifiability, in addition to the properties in the CIA triad.

Grüße, Carsten