What it means
Assurance comes from evidence such as disciplined engineering, analysis, testing, independent review, provenance, configuration control, operational monitoring, and trustworthy decision records.
Why it matters
A control may exist without working reliably. Assurance asks how much confidence decision makers should place in claims about the system and why that confidence is warranted.
Practical focus
- Define the security claims that require evidence
- Match assurance rigor to consequence and uncertainty
- Use diverse evidence rather than one test
- Maintain assurance as the system changes
Common mistakes
- Treating certification as permanent assurance
- Equating documentation volume with confidence
- Ignoring the trustworthiness of tools and evidence sources
- Testing only expected behavior
Certification relevance
This subject appears in or supports the following certification bodies of knowledge: