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<p class="MsoNormal"><span style="mso-fareast-language:EN-US">Hi John,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US">>>> </span>If a requirement isn't testable.. then how would you possibly know if you have achieved it or not?<o:p></o:p></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US">That’s the security challenge we face in today’s world.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US">You can define and pass a set of tests. But you cannot be certain tests provide coverage of all possible attack paths, unless you start using formal methods (which become a significant cost).<o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial",sans-serif">Regards,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial",sans-serif"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial",sans-serif">Colin Robbins
<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial",sans-serif">Nexor<br>
<b><span style="color:#72349D">Tel:</span></b><span style="color:black"> +44 (0) 115 953 5541<o:p></o:p></span></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><b><span lang="EN-US">From:</span></b><span lang="EN-US"> trustable-software [mailto:trustable-software-bounces@lists.trustable.io]
<b>On Behalf Of </b>Munns, Jon<br>
<b>Sent:</b> 03 January 2018 10:52<br>
<b>To:</b> Trustable software engineering discussion <trustable-software@lists.trustable.io><br>
<b>Subject:</b> Re: [trustable-software] Exploring the "Hypothesis for software to be trustable"<o:p></o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">On 3 January 2018 at 10:39, Colin Robbins <<a href="mailto:Colin.Robbins@nexor.com" target="_blank">Colin.Robbins@nexor.com</a>> wrote:<o:p></o:p></p>
<blockquote style="border:none;border-left:solid #CCCCCC 1.0pt;padding:0cm 0cm 0cm 6.0pt;margin-left:4.8pt;margin-right:0cm">
<p class="MsoNormal">Hi Paul,<br>
<br>
Happy new year to you.<br>
<br>
I think the approach looks good where the outcome is deterministic. I.e., there are t.tests for each t.requirement.<br>
<br>
On to the attributes of trustable is secure. The challenge with secure, is that it non-deterministic, and changes over time.<br>
So I suggest we need to add an element of "when" the tests were performed, and the state of the "known set of vulnerabilities" at that time.<br>
<br>
Regards,<br>
<br>
Colin Robbins<br>
Nexor<br>
Tel: +44 (0) 115 953 5541<br>
<br>
-----Original Message-----<br>
From: trustable-software [mailto:<a href="mailto:trustable-software-bounces@lists.trustable.io">trustable-software-bounces@lists.trustable.io</a>] On Behalf Of Paul Sherwood<br>
Sent: 02 January 2018 10:41<br>
To: <a href="mailto:trustable-software@lists.trustable.io">trustable-software@lists.trustable.io</a><br>
Subject: [trustable-software] Exploring the "Hypothesis for software to be trustable"<br>
<br>
Hi folks,<br>
over the break I was thinking about the hypothesis that Edmund expressed last year [1], and found myself attempting to codify some of the context and underlying assumptions, as you can see below.<br>
<br>
I've gone for a shorthand of t.* to denote things that seem to be either required or implied by the 'Trustable Software' discussions and concepts.<br>
<br>
Note that:<br>
- I'm not even confident yet that the hypothesis is generally correct.<br>
- I think that the specifics of the hypothesis are probably not all correct<br>
- I'm completely sure that following statements contain bugs and I would appreciate any/all review feedback<br>
<br>
br<br>
Paul<br>
<br>
# t.software<br>
<br>
- we assess the trustability of t.software based on t.evidence<br>
- t.software MUST have t.requirements<br>
- t.software MUST satisfy its t.requirements<br>
- there MUST be t.measurable t.evidence that t.software satisfies its t.requirements<br>
<br>
# t.requirements (derived from wikipedia [2])<br>
<br>
- t.requirements MUST be unitary<br>
- t.requirements MUST be atomic (non-conjugated)<br>
- t.requirements MUST be complete<br>
- t.requirements MUST be consistent<br>
- t.requirements MUST be traceable<br>
- t.requirements MUST be current<br>
- t.requirements MUST be unambiguous<br>
- t.requirements MUST be verifiable<br>
- t.requirements MAY be graded by priority/importance<br>
<br>
# t.tests<br>
<br>
- t.requirements MUST exist<br>
- all t.requirements MUST have t.tests<br>
- all t.tests MUST pass<br>
- the scope of the t.requirements MUST be t.measurable<br>
- the scope of the t.tests MUST be t.measurable<br>
- we MAY t.estimate the scale or scope of missing t.requirements<br>
- we MAY t.estimate the scale or scope of missing t.tests<br>
<br>
# t.evidence<br>
<br>
- t.evidence is machine-parseable metadata associated with t.software<br>
- t.evidence MUST include t.evidence of its own integrity/correctness<br>
- t.evidence MUST include t.identity for author(s)<br>
- t.evidence MUST include t.identity for committer/uploader<br>
- t.evidence MUST include creation/modification/commit time-and-date<br>
- t.evidence MAY include text description and/or comments<br>
- t.evidence MAY include t.identity for reviewer(s)<br>
- t.evidence MAY include t.identity for review comments<br>
<br>
<br>
# t.identity, t.identify<br>
<br>
- t.identity is a kind of t.evidence<br>
- t.identity MUST map to a single t.contributor<br>
- a t.contributor is a uniquely identifiable person, organisation or software program<br>
- t.contributors contribute to t.software and/or t.evidence<br>
- t.contributors are responsible and accountable for their contributions<br>
<br>
# t.measure, t.measureable, t.estimate, t.measurement, t.metrics<br>
<br>
- t.measurements MUST be derived from t.evidence via automation<br>
- t.estimates MUST be derived from t.evidence via automation<br>
- t.measurements MUST be believed to be factually correct<br>
- t.estimates are known to be uncertain<br>
- we t.measure all available t.evidence about t.software, producing t.metrics<br>
- we t.measure multiple t.metrics, including signals for some (ideally<br>
all) of<br>
- engineering cost/effort<br>
- project scale<br>
- project value<br>
- project quality<br>
- project software performance/efficiency<br>
- we use t.estimates to check t.measurements or fill in gaps in t.evidence<br>
- we look conflicts between t.metrics<br>
- we evaluate the conflicts<br>
- we aim to identify gaps in t.metrics<br>
- we seek new t.evidence to close them<br>
- all t.metrics MUST be meaningful<br>
- for t.software, all t.metrics are acceptable<br>
- we can aggregate/manipulate t.metrics to provide a t.measure of trustability<br>
<br>
# t.provenance<br>
<br>
- t.evidence MUST t.identify the authors of the t.software<br>
- t.evidence MUST t.identitify the reviewers of the t.software<br>
- t.evidence MUST t.identify the integrators/mergers of the t.software<br>
- FIXME add hypothesis provenance logic here<br>
<br>
# t.change<br>
<br>
- a t.change is is any change to standards, requirements, tests, code,<br>
documentation, or other materials that affect the project<br>
- a t.change specifically includes the initial upload of any component of any<br>
materials<br>
<br>
# t.build<br>
<br>
- a t.build consists of any compilation, reformation, rearrangement,<br>
or copying of any sources to generate any artefacts that may become<br>
subject to test or deployment<br>
- FIXME add hypothesis build logic here<br>
<br>
# t.process, t.effect, t.friction, t.value<br>
<br>
- t.process is a set of practices to increase the trustability of software<br>
- adding t.process to a project MUST lead to t.measurable t.effects<br>
- t.effects are t.measures and/or t.metrics<br>
- t.friction is negative t.effects<br>
- t.value is positive t.effects<br>
- the t.effects of adding t.process to any project MUST be t.measurable<br>
- adding t.process to a mature infrastructure project must<br>
- provide t.measurable t.value<br>
- involve acceptable (minimal) t.friction<br>
- be justifiable to be used upstream and/or<br>
- be applicable downstream<br>
<br>
# t.reproduce<br>
<br>
- FIXME add hypothesis reproduction logic here<br>
<br>
# t.function<br>
<br>
- FIXME add hypothesis functionality logic here<br>
<br>
# t.update<br>
<br>
- FIXME add hypothesis update logic here<br>
<br>
# t.context<br>
<br>
- t.context is written information which states or clarifies relevant ideas for t.software<br>
- [trustable software<br>
discussions](<a href="https://lists.trustable.io/pipermail/trustable-software/" target="_blank">https://lists.trustable.io/pipermail/trustable-software/</a>)<br>
- [wikipedia requirement](<a href="https://en.wikipedia.org/wiki/Requirement" target="_blank">https://en.wikipedia.org/wiki/Requirement</a>)<br>
- [RFC 2119](<a href="https://www.ietf.org/rfc/rfc2119.txt" target="_blank">https://www.ietf.org/rfc/rfc2119.txt</a>)<br>
- virtually all existing software does not satisfy the [trustable software<br>
hypothesis](<a href="https://gitlab.com/trustable/overview/wikis/hypothesis-for-software-to-be-trustable" target="_blank">https://gitlab.com/trustable/overview/wikis/hypothesis-for-software-to-be-trustable</a>)<br>
- but a lot of software is widely trusted<br>
- to be useful, the t.software concepts must be<br>
- easy to understand<br>
- justifiable<br>
- practical and realistic<br>
- applicable to existing software<br>
- collecting t.evidence needs to be low friction<br>
- t.measures and t.metrics for widely trusted software existing software should be good<br>
<br>
<br>
[1]<br>
<a href="https://gitlab.com/trustable/overview/wikis/hypothesis-for-software-to-be-trustable" target="_blank">https://gitlab.com/trustable/overview/wikis/hypothesis-for-software-to-be-trustable</a><br>
[2] <a href="https://en.wikipedia.org/wiki/Requirement" target="_blank">https://en.wikipedia.org/wiki/Requirement</a><br>
<br>
<br>
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<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial",sans-serif;color:#222222;background:white">Kind Regards,</span><o:p></o:p></p>
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<p class="MsoNormal" style="background:white"><span style="font-size:10.0pt;font-family:"Arial",sans-serif;color:#222222">Jon Munns MBA<o:p></o:p></span></p>
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