Zero-Trust Device Management

1. Mechanism and Primitive Description

Zero-trust device management within the spatial mesh treats every device as untrusted on every operation. Enrollment, prior good behavior, network position, and ownership are not sufficient to admit a device action; only a current, chain-credentialed attestation suffices. The attestation surface is composite, drawing on multiple physical and software-layer evidence sources whose individual admissibility is weighted under the governance chain.

Three principal evidence classes anchor device attestation. Physical-unclonable-function (PUF) challenge-response provides hardware-rooted identity: a credentialing authority issues challenges whose responses depend on manufacturing-variation entropy unique to the device, producing an unforgeable identity proof that survives firmware compromise. Tamper-evident seal observations — physical seals, intrusion sensors, environmental witnesses (temperature excursion, supply-voltage glitches, light exposure on shielded surfaces) — provide continuous physical-integrity attestation reported by credentialed observers. Software bill-of-materials (SBOM) attestation enumerates the firmware and software components currently executing on the device, signed by the device's secure-boot chain and cross-checked against the credentialed manufacturer's release manifest and any vulnerability disclosures admitted to the chain.

Composite admissibility fuses these into a single device-admissibility determination evaluated continuously. A device with valid PUF response but compromised tamper seals fails admissibility; a device with intact seals but an SBOM containing a known-vulnerable component fails admissibility under the configured policy; a device with current evidence across all three classes is admitted only for the operational scope its credential authorizes. Governed actuation conditions every device-mediated operation — sensor reading, actuator command, mesh-message origination, key-material use — on the current admissibility state. Lineage records each attestation, each admissibility evaluation, and each resulting actuation; a later forensic review can reconstruct exactly what evidence justified a device's admission at any moment.

The structural exclusion property is essential. When admissibility lapses, the device does not receive an alert that an operator may choose to act upon; the device is removed from governed actuation immediately and structurally. This distinguishes the pattern from monitoring-and-response architectures in which compromised devices may continue producing observations and accepting commands while a response workflow proceeds in parallel. Under the disclosed pattern, the response is the lapse: there is no window during which a structurally inadmissible device continues to operate within the mesh.

2. Operating Parameters and Engineering Envelope

Attestation freshness windows are configured per device class and operational risk. A safety-critical actuator may require sub-second PUF challenge responses; a low-stakes environmental sensor may operate under minute-scale freshness. Tamper-seal observations operate continuously where instrumented and at periodic inspection cadence where physical witness is required. SBOM attestation typically refreshes on every secure-boot event and on every authorized update, with intermediate revalidation triggered by published vulnerability disclosures admitted to the chain.

Corroboration thresholds vary by deployment posture. A defense or critical-infrastructure deployment may require all three evidence classes to be current; a less-stringent deployment may admit operation under two-of-three with declared degradation. Authority-trust coefficients allow the federation to weight a device-manufacturer credential, a deployment-operator credential, and a third-party attestation-service credential differently, with weights themselves chain-recorded and revisable under governance procedures.

Admissibility-lapse handling defines structural exclusion. A device whose attestation lapses is removed from governed actuation immediately; pending operations originating from the device are quarantined pending re-attestation; downstream operations that depend on that device's recent observations may have their own admissibility re-evaluated under reduced corroboration. Renewal requires fresh evidence across the lapsed classes; a device cannot return to admitted state by simply re-presenting an old credential.

Engineering trade-offs include attestation overhead (typically a few percent of device compute and bandwidth budget for periodic attestation; higher for continuous PUF challenges), supply-chain coupling (manufacturers must support credentialed PUF and SBOM emission), and revocation latency (compromised-component disclosures must propagate to the chain within bounded windows to be effective). The envelope tolerates intermittent connectivity through bounded-staleness operation: a device may continue executing locally against last-known-admissible state for a declared offline window before structural exclusion engages.

3. Alternative Embodiments

Embodiments span industrial-control devices (PLCs, RTUs, smart sensors), defense and dual-use platforms (sensor pods, autonomous vehicles, weapon-system components), medical-device deployments (infusion pumps, imaging modalities, networked monitors), commercial IoT (energy, transport, building automation), and computing infrastructure (servers, network appliances, cryptographic modules). Each embodiment instantiates the same composite-attestation structure with class-appropriate evidence sources and freshness policies.

Evidence-class embodiments may substitute or supplement. A device lacking PUF hardware may use a hardware-security-module-bound identity with equivalent unforgeability properties; a device without environmental tamper sensors may rely on physical inspection witness from credentialed personnel; an embedded device incapable of full SBOM emission may use a manufacturer-attested measurement of its boot-chain hash. Federation embodiments include single-operator deployments, coalition deployments where multiple authorities cross-recognize device credentials, and supply-chain embodiments in which the manufacturer, integrator, deploying operator, and using authority each contribute credentialed evidence.

Operational embodiments include continuous-connectivity deployments (real-time admissibility evaluation), intermittent-connectivity deployments (bounded-staleness operation), and air-gapped deployments (out-of-band attestation transport with chain-anchored summaries). The structural form is preserved across all of these.

Embodiments with mixed-trust device populations are also supported. A deployment may admit some devices under full three-class attestation and others under reduced-class attestation with correspondingly restricted operational scope; the chain records the scope restriction so that downstream operations evaluate device contributions against the actual admissibility class rather than against a deployment-wide trust assumption. Legacy-device embodiments may use a credentialed gateway that observes the legacy device's behavior and attests on its behalf, with the gateway's own admissibility chain-recorded.

4. Composition With Adjacent Primitives

Zero-trust device management composes with the mesh's broader observation, weighting, admissibility, actuation, and provenance primitives by treating device attestation as one class of credentialed observation that the chain admits and weights. A device that is itself an observer (sensor, monitor) feeds two streams to the chain: the operational observation and the device's own admissibility attestation. Downstream admissibility evaluations consider both.

Cross-mesh zero-trust federation composes by allowing a device credentialed in one mesh to be admitted to a federated mesh under declared cross-recognition; the device's lineage thread crosses the federation boundary as first-class chain history. Byzantine-robust admissibility composes by requiring multi-source attestation thresholds that survive bounded fractions of compromised attestation authorities or compromised observers — a single-attestation-source compromise cannot itself admit a compromised device.

Dispute-mechanism composition treats admissibility disputes — a device claiming wrongful exclusion, an operator claiming a device should not have been admitted — as appellate evaluations against the chain-recorded evidence. Composition with the marketplace primitives allows devices to participate as credentialed parties in capacity, spectrum, or compute marketplaces only while their device-admissibility is current; revocation cascades to outstanding marketplace commitments under declared procedures.

Composition with federated-skill-training primitives ensures that contributions to shared adaptations originate only from currently-attesting devices, foreclosing a class of supply-chain attacks in which compromised edge devices poison aggregated models. Composition with the broader observation-and-actuation pipeline allows device admissibility to influence not only the device's own actuations but the admissibility weighting of any downstream computation that consumed its observations — a discovered compromise propagates to invalidate dependent decisions under declared retroactive-admissibility procedures.

5. Prior-Art Distinctions

Conventional zero-trust network architectures (ZTNA, BeyondCorp-pattern systems) apply never-trust-always-verify to user and application traffic but treat device identity as a relatively static enrollment property, evaluated against device-posture checks at session establishment. The disclosed pattern is structurally distinct: device admissibility is a continuously-evaluated, chain-recorded property fused from physical, hardware, and software evidence under composite admissibility, not a session-time posture assessment.

Trusted-platform-module attestation and remote-attestation protocols (e.g., DICE-pattern attestation, TPM quote schemes) provide hardware-rooted measurement but do not by themselves constitute the joint chain. The disclosed pattern uses such measurements as one input to a composite admissibility evaluation that also weights tamper observations, SBOM admissibility, and credentialing authority standing under chain governance.

SBOM-based supply-chain security frameworks address component disclosure and vulnerability tracking but do not couple SBOM evidence to continuous admissibility-conditioned operation. PUF-based authentication systems provide identity but not the broader admissibility composition. The disclosed pattern's distinction is the joint, chain-recorded composition of PUF, tamper-evidence, and SBOM under the five-property governance chain, with structural exclusion on lapse rather than alerting-based response.

6. Disclosure Scope

The disclosure encompasses zero-trust admission of physical devices to an operational mesh under the five-property governance chain, with composite admissibility evaluating PUF challenge-response (or equivalent hardware-rooted identity), tamper-evident observations (physical and environmental), and SBOM attestation (or equivalent firmware-and-software inventory). The scope reaches embodiments across device classes, evidence-class substitutions where principled equivalence holds, and federation breadths from single-operator to coalition.

The scope reaches embodiments in which freshness windows, corroboration thresholds, and admissibility rules vary by device class and operational risk, provided the structural exclusion property is preserved — an inadmissible device cannot continue governed operation. It reaches embodiments coupling device admissibility to adjacent mesh primitives (observation, marketplace participation, actuation) through shared lineage.

The scope does not reach session-time-only zero-trust postures lacking continuous admissibility evaluation, attestation systems lacking chain-recorded provenance, or systems in which admissibility lapse produces alerting alone without structural exclusion. It also does not reach systems relying on a single evidence class without composite admissibility, since the joint operation of physical, hardware, and software evidence is essential to the pattern. The disclosure preserves room for evolution of attestation protocols, PUF hardware classes, and SBOM standards under the federation's declared governance procedures.