The book reframes cybersecurity as an engineering discipline grounded in structure rather than an arms race of secrets, tools, and telemetry. It brings QIQD into security practice as a geometry of trust: deep structure remains non-exportable, observable surfaces are governed, and evidence strengthens assurance without becoming a reconstruction path. Quantum no-go results become interface laws for controlled disclosure, continuity, and proof. PQC is the scalable cryptographic substrate, QKX/QKD a selective high-assurance link overlay, QRNG an entropy service, and QIQD-minted seeds the root authority. Across four parts, the book moves from no-go theorems, projected uniqueness, qualified determinism, and commuting receipts to operational controls for integrity, uncertainty, and entanglement. It then develops PAR/MAR imprints, qibits, STEG-Fabric, task-restricted controllers, watchdog attestation, a quantum security chip, and the QCSDC simulator. The result is assurance by design.
