When Does AI Supervision Help? A Role-Aware Study of Network Fraud Decision Management with Blockchain Auditability

Artificial intelligence (AI)-enabled security decision systems in telecom and IoT networks can draw on heterogeneous models whose outputs may trigger operational actions. Recording such decisions on a blockchain does not establish that they are authorised, applicable, policy-consistent, or still valid at execution time. This paper presents governance-2, an authority-bound and fail-closed architecture that separates upstream scientific decision formation from downstream operational enforcement. Each governed case is bound to registered dataset, model, policy, deployment, and optional refiner authorities. Smart-contract checks enforce role separation, authority compatibility, score-to-state and state-to-action consistency, lifecycle validity, replay protection, pause control, authority revocation, and exact-action execution. Evaluation uses two independent branches: a controlled spectrum-access replay with four frozen heterogeneous decision configurations and a measured radio-frequency branch based on WiFiSpectralJam. Across eight frozen measured-data decision streams, governance-2 processes 153,744 stream-case instances derived from 19,218 measured captures while preserving interference-specific semantics and unresolved review states. The full contract rejects all tested invalid operations; stateful invariant testing completes 2,000 generated transaction sequences with zero invariant violations; and single-capability ablation shows that removing an enforcement family exposes its assigned invalid operations while unrelated protections remain active. The results indicate that heterogeneous AI security decisions can share a common governance plane across telecom and IoT settings without redefining their scientific semantics.

In enterprise fraud detection, model accuracy alone is insufficient when insiders can tamper with audit logs or bypass approval workflows. Real-world incidents show that fraud often persists not because detection algorithms fail, but because the audit trail itself is controllable by privileged operators. This exposes a fundamental trust gap: who audits the auditor? We present a tamper-evident fraud detection system that anchors both ML predictions and workflow execution to an immutable blockchain ledger. Rather than using blockchain as passive storage, we enforce the entire approval process through smart contracts, ensuring that every transaction, prediction, and explanation is atomically recorded and cannot be retroactively modified. Our detection module achieves competitive accuracy (F1 = 0.895, PR-AUC = 0.974) while providing cryptographically verifiable decision trails that support regulatory auditability requirements (e.g., GDPR Article 22). System evaluation shows sub-25 ms inference latency and economically viable deployment on Layer-2 networks at under $0.01 per transaction (validated against PolygonScan data), supporting enterprise-scale workloads of 10,000+ monthly payments.

Decentralized finance exposes supervisors to fast-moving, networked credit risks. General-purpose LLM agents fit this setting poorly: they over-read weak evidence and recommend high-stakes interventions, while existing evaluations offer no regulator-aligned way to measure the resulting false alarms. We introduce DeXposure-Claw, a forecast-grounded agentic supervision system that routes LLM decisions through structured evidence: (1) DeXposure-FM, a graph time-series foundation model, forecasts future exposure networks; (2) deterministic monitors and stress scenarios then turn those forecasts into typed alerts, attribution signals, and scenario evidence; and (3) data-health and confidence gates constrain escalation before DeXposure-Claw emits auditable supervisory tickets with rationales. We further develop DeXposure-Bench, a six-axis evaluation harness, whose decision axis scores tickets against a regulator-aligned absolute-loss ground truth and an explicit false-intervention rate. Experiments on five years of weekly real data fully support our system. Code is at https://github.com/EVIEHub/DeXposure-Claw.