Phase 6 Sprint 6.1 - Immutable Logging Architecture

Summary

A tamper-evident append-only log chain now records telemetry gateway outcomes and periodically emits seal snapshots.

Threat Model

• Assume history rewrite attempts may occur post-incident.

Attack Vectors Considered

• Entry modification.
• Hash-link bypass.
• Silent log truncation.

Mitigations Implemented

• Append-only record writes.
• Previous-hash linkage across entries.
• Deterministic entry hash verification.
• Periodic seal entries (log.sealed) for checkpointing.

Residual Risk

• Local-only chain without external anchoring.

Future Improvements

• Remote chain anchoring and audit attestation workflows.

Architecture Diagram

flowchart LR
  GW[Telemetry Gateway]
  LOG[(tamper_audit.jsonl)]
  VERIFY[Integrity Verifier]
  SEAL[Periodic Seal Entry]

  GW --> LOG
  LOG --> VERIFY
  LOG --> SEAL