Proposal: Safety Integrity Classification (SIC) — A Cross-Domain Normalized Abstraction for CycloneDX 2.0

Thanks again for the detailed feedback @stevespringett . Based on your comments, a more focused proposal is a **Safety Integrity Classification (SIC)** that complements the existing 2.0 risk, perspective, and criticality constructs rather than introducing separate safety metadata.

## Motivation

CycloneDX 2.0 already provides:

* Safety and societal impact categories
* Safety-oriented domains
* Component-to-risk relationships
* VEX integration
* Criticality and asset classifications

What appears to be missing is a machine-readable abstraction for expressing **safety integrity levels** across industries.

## Goal

Provide a normalized classification that can represent industry-specific safety assurance schemes while remaining attached to existing CycloneDX constructs.

Examples include:

| Domain | Standard | Classification |
| ---------- | --------- | -------------- |
| Automotive | ISO 26262 | ASIL A-D |
| Industrial | IEC 61508 | SIL 1-4 |
| Aviation | DO-178C | DAL A-E |
| Medical | IEC 62304 | Class A-C |
| Rail | EN 5012x | SIL mappings |

A normalized abstraction could look like:

```yaml
safetyIntegrity:

classification:
scheme: ISO26262
level: ASIL-D

normalizedLevel:
HIGH
```

or

```yaml
safetyIntegrity:

classification:
scheme: IEC61508
level: SIL-3

normalizedLevel:
HIGH
```
## Integration with Existing 2.0 Constructs

Rather than existing independently, `safetyIntegrity` would attach to existing constructs such as:

* assetClassification
* risk
* blueprint
* component

For example:

```yaml
component:
name: brake-controller

assetClassification:
criticality: critical

safetyIntegrity:

classification:
scheme: ISO26262
level: ASIL-D

risk:

domain:
automotive-safety

impact:
physical

relatedVulnerabilities:
- CVE-XXXX

vex:
state: affected
```
This enables downstream tooling and policy engines to reason about safety context.

Example:

```text
if safetyIntegrity.normalizedLevel >= HIGH
and vex.state == affected
then priority = immediate
```

I think this preserves the existing CycloneDX 2.0 design while introducing a common abstraction for safety assurance levels across domains. Interested to hear whether this direction aligns with the 2.0 roadmap.

Start by reviewing the CycloneDX 2.0 risk, perspective, criticality, assetClassification, blueprint, component, and VEX constructs described in the proposal. Determine whether a normalized safety-integrity abstraction fits the existing model; done requires an agreed roadmap and concrete specification scope before implementation can begin.

Written by the indexing model from the issue text.