RFC-PCS-0005

 

PCS Reference Implementation Requirements

Status: Draft

Intended Status: Standards Track

Updates: RFC-PCS-0001, RFC-PCS-0002, RFC-PCS-0003, RFC-PCS-0004

Expires: TBD

 

1. Abstract

This document defines the requirements and constraints for a Persistra Cognitive Standard (PCS) Reference Implementation.

 

The PCS Reference Implementation provides a canonical, non-normative realization of PCS specifications intended to:

• Demonstrate PCS feasibility
• Clarify ambiguous implementation details
• Establish baseline behavioral expectations
• Support conformance testing and certification

 

This document explicitly distinguishes reference behavior from normative requirements.

 

2. Motivation

Open standards require reference implementations to ensure consistent interpretation and interoperability.

 

However, reference implementations that expose internal architecture risk:

• Fragmentation through forks

• De facto standard capture by third parties

• Uncontrolled propagation of patented mechanisms

 

RFC-PCS-0005 defines a reference implementation model that balances:

• Transparency

• Reproducibility

• Architectural neutrality

• Intellectual property protection

 

3. Scope

This document applies to any implementation designated as a PCS Reference Implementation.

 

It does not mandate that PCS adopters use the Reference Implementation.

 

4. Definitions

Reference Implementation (RI): A canonical, illustrative implementation

• Normative Requirement: A MUST/SHALL condition from PCS RFCs
• Behavioral Equivalence: Observable output consistency
• Internal Mechanism: Implementation-specific internal logic
• Normative language follows RFC 2119.

 

5. Role of the PCS Reference Implementation

The PCS Reference Implementation exists to:

• Demonstrate PCS compliance pathways
• Validate PCS-CTS conformance expectations
• Serve as interoperability benchmark
• Reduce ambiguity in PCS interpretation

 

The Reference Implementation does not define PCS requirements.

 

6. Reference Implementation Requirements

6.1 Behavioral Fidelity

The Reference Implementation MUST:

• Exhibit PCS-compliant external behavior
• Pass PCS-CTS tests for PCS-L1 through PCS-L4 (where supported)
• Enforce CMCC invariants

 

6.2 Architectural Non-Normativity

The Reference Implementation MUST NOT:

• Impose internal architecture requirements
• Define mandatory data structures
• Prescribe algorithmic strategies

 

7. Implementation Boundaries

7.1 Observable Interfaces

The Reference Implementation MUST expose:

• PCS-compliant APIs
• Deterministic policy enforcement behavior
• Provenance generation interfaces

 

7.2 Internal Opacity

Internal mechanisms MAY be:

• Abstracted
• Stubbed
• Modularized

 

Implementers MUST NOT assume internal mechanisms are required for compliance.

 

8. Licensing Model

The PCS Reference Implementation MAY be released under a permissive software license.

Such licensing:

• Applies only to source code
• Does not grant patent rights
• Does not confer PCS certification

 

9. Relationship to PCS-CTS

The Reference Implementation:

• MUST pass PCS-CTS at declared levels
• SHOULD be used to validate PCS-CTS updates
• MAY serve as regression benchmark
• PCS-CTS remains authoritative for compliance determination.

 

10. Versioning and Stability

10.1 Version Alignment

The Reference Implementation MUST declare:

• PCS version supported
• PCS-CTS version used
• CMCC version enforced

 

10.2 Stability Guarantees

Backward compatibility SHOULD be maintained where feasible.

 

11. Prohibited Uses

The PCS Reference Implementation MUST NOT be:

• Marketed as PCS certification
• Represented as the only compliant implementation
• Used to claim PCS compliance without passing PCS-CTS

 

12. Intellectual Property Considerations

12.1 Patent Scope

Implementation of PCS features MAY require licenses to patents held by Persistra or other parties.

 

12.2 No Implied License

Use of the Reference Implementation does NOT grant:

• Patent licenses
• Certification rights
• Trademark rights

 

13. Security Considerations

The Reference Implementation SHOULD:

• Isolate test and production modes

• Protect provenance and audit artifacts

• Prevent tampering with conformance evidence

 

14. Governance

Designation of an implementation as an official PCS Reference Implementation is controlled by the PCS Spec Editor.

 

Multiple reference implementations MAY exist.

 

15. IANA Considerations

This document defines no IANA actions.

 

16. Conclusion

The PCS Reference Implementation provides a shared point of reference without constraining innovation or surrendering control.

 

It enables ecosystem growth while preserving architectural independence.

 

End of RFC-PCS-0005