Records & Traceability
UNECE R156 requires complete, accurate, and tamper-resistant records for every software update. This page outlines how to establish end-to-end traceability from change request to in-field result, so you can demonstrate conformity during audits and incident investigations.
Purpose
- Prove that updates were authorized, secure, eligible, and correctly installed.
 - Enable root-cause analysis, rollback decisions, and regulatory reporting.
 - Maintain per-VIN and per-software-item history across the lifecycle.
 
Traceability Model (End-to-End)
Maintain bidirectional links between these entities (stable IDs, timestamps, owners):
- Change ⇄ Build ⇄ Package & Signature ⇄ Campaign ⇄ Eligibility Decision ⇄ VIN/ECU Outcome ⇄ Post-Update Validation
 - Include toolchain versions, hashes, key IDs, and approver identities at each step.
 
Minimum Record Set (Per Campaign)
- Authorization: approvals, roles, segregation evidence, policy references.
 - Artifacts: binaries, manifests, SBOM, hashes, signatures, signer IDs, timestamps.
 - Eligibility: rules used, VIN/ECU targeting snapshots, dependency checks, market constraints.
 - Rollout: cohorts, start/stop times, pause/resume/rollback triggers and decisions.
 - Validation: acceptance criteria, results, dashboards/screenshots with dates.
 - Comms: dealer bulletins, customer notices, authority filings (ids, dates, locales).
 
Minimum Record Set (Per VIN / ECU)
- VIN, ECU ID, software item ID, prior version → new version.
 - Eligibility decision (rule version, dependency status) with timestamp.
 - Install outcome (success/fail/partial), error codes, retries, duration.
 - Signature/verification result, anti-rollback counter state.
 - Post-update health snapshot (key DTC summary, self-tests).
 - Rollback/abort flag and linkage to incident ticket if applicable.
 
Integrity, Authenticity & Non-Repudiation
- Store hashes of artifacts and signature metadata (algorithm, key ID, time).
 - Protect logs at rest (append-only/WORM or signed logs); keep clock sync evidence.
 - Retain key lifecycle events (rotation, revocation) that affect verification.
 
Retention & Access Control
- Define retention per market (vehicle lifetime + legal buffer); document purging rules.
 - Restrict access on a least-privilege basis; audit all access and exports.
 - Encrypt sensitive fields (e.g., device credentials) and separate PII from technical logs when possible.
 
Privacy & Data Minimization
- Log only what is necessary to prove conformance and support investigations.
 - Maintain a data inventory and DPIA/records of processing where required.
 - Expose self-service export/delete pathways where mandated by local law.
 
Tooling & Process Controls
- Evidence Index: single, navigable index of all artifacts with stable IDs and owners.
 - Versioned schemas: strict schemas for campaign/VIN records; validate on write.
 - Automation: auto-attach signatures, hashes, and tool versions from CI/CD.
 - Backups: immutable, geo-redundant backups; periodic restoration drills.
 
Reporting & Dashboards
- Per-campaign KPIs: success rate, retry/abort rate, install duration, post-update incident rate.
 - Compliance widgets: % VINs updated, lagging cohorts, unresolved failures, rollback count.
 - Export packs: time-stamped snapshots for authorities (PDF/CSV with manifest and hashes).
 
Practical Do / Don’t
Do
- Use immutable IDs for artifacts and link them everywhere.
 - Capture signer identity and tool versions at packaging time.
 - Snapshot eligibility rules used for each VIN decision.
 - Auto-attach health/DTC summaries to the per-VIN record.
 - Time-box exports for audits with a signed manifest of files and hashes.
 
Don’t
- Rely on mutable spreadsheets as the system of record.
 - Store excessive PII in telemetry when technical IDs suffice.
 - Mix dev/test artifacts with production records.
 - Let key rotations break replay of historical verifications—retain old trust anchors.
 
Typical Outputs / Evidence
- Evidence Index (IDs, owners, versions, applicability) and schema definitions.
 - Campaign archives (artifacts, manifests, hashes, signatures, approvals).
 - Eligibility snapshots and per-VIN/ECU outcomes with validation results.
 - Immutable logs/WORM snapshots; key lifecycle and clock-sync records.
 - Privacy/retention policy, access control audit logs, and export packs for authorities.
 
                        Disclaimer: This page summarizes records and traceability expectations under UNECE R156.
                        For authoritative requirements, consult the regulation text and your approval authority’s guidance.