# Assurance Boundary

This artifact is a research demonstrator. The following statements bound exactly
what is and is not claimed.

## What is claimed

- The emulator runs real Web Crypto primitives (ECDSA P-256/P-384, SHA-256,
  HKDF) in the browser.
- PCR measurement chains, audit-ledger signing, tier transitions, quorum spawn,
  zero-trust tokens, and the failure-mode scenarios behave as described and are
  reproduced by the bundled test suite (275 deterministic checks).
- The trace verifier re-derives PCR chains, verifies the ECDSA signature on every
  audit entry against the trace's own embedded signing key, and validates a
  P-384 signed anchor (event count + final PCR digests + trace SHA-256).
- With an out-of-band identity pin, the verifier resists adversarial trace
  forgery, including anchor re-key attacks.

## What is NOT claimed

- Not certified hardware. No FIPS 140, Common Criteria / EAL, NSA, NASA, or DoD
  endorsement, validation, or certification of any kind.
- Silicon timing (I2C/SPI byte latency, hold-up capacitor energy, boot RTM) is
  modeled, not measured on physical silicon.
- PQC / ML-DSA fields model interface shape and evidence packaging only. No
  certified or complete ML-DSA implementation is bundled in this artifact.
- Radiation (SEU/ECC), electronic-warfare, and Byzantine behaviors are scenario
  models, not physical laboratory validation.
- Technology Readiness Level is approximately 3-4 (research demonstrator). No
  hardware coupon is included.

## Cryptographic trust root

The audit anchor's attestation public key travels inside the evidence file. It is
therefore NOT a trust root on its own. Adversarial forgery resistance requires the
verifying party to pin the device's attestation identity out-of-band (for example,
from a separately distributed identity certificate). Absent that pin, the verifier
honestly reports "integrity-and-same-session" trust.