Quantum Key Distribution (QKDN) Security

As telecommunications transitions towards 6G / IMT-2030, the vulnerability of current asymmetric cryptography (RSA, ECC) to Shor's Algorithm mandates the integration of Quantum-Safe architectures. itu-t Series Y.3800 defines the functional requirements for Quantum Key Distribution Networks (QKDN).

🏛️ Functional Architecture (Y.3802)

The QKDN consists of three logical layers that provide secure keys to the standard data network (e.g., 5G Core).

graph TD
    subgraph QKDN [Quantum Key Distribution Network]
        QL[Quantum Layer] --> QKL[Key Management Layer]
        QKL --> QCL[Control/Management Layer]
    end
    
    subgraph UserNet [User Data Network]
        5GC[5G Core / Edge]
    end
    
    QKL -- "Secure Keys" --> 5GC

📑 Technical Mappings

Recommendation	Technical Scope	Security Mapping
Y.3802	Functional Architecture	Defines the QKD Node (QN) and Key Manager (KM).
Y.3803	Key Management	Requirements for Key Authentication and Integrity.
Y.3813	SDN-Control for QKDN	Securing the Software Defined controller of quantum links.
X.1811	Security Requirements	Common security requirements for QKDN nodes (Auth, DoS).
X.1812	Security Audit of QKDN	Detailed procedures for auditing a quantum node's physical layer.

🔐 Key Security Requirements (X.1811)

Node Authentication: All QKD nodes must perform mutual authentication before establishing a quantum link.
Key Integrity: Measures to prevent a "Man-in-the-Middle" from tampering with the key-sifting process.
Denial-of-Service (DoS): Protecting the quantum channel from high-power interference (noise) that disrupts entanglement.
Forward Secrecy: Ensuring that even a future quantum computer cannot decrypt past traffic if a node is compromised.

🛡️ Tactical Domain Mapping: Quantum-Safe Security

Area / Component	Functional Security Objective	ITU Rec (Official PDF)	3GPP Equiv
Key Extraction	Error-Correction & Sifting Sec	Y.3803	TR 33.841
KM Interface	Secure Key Delivery to App	X.1710	TS 33.501 (PQC)
Physical Sec	Side-Channel & Trojan-Horse	X.1714	NIST PQC Alt
QKDN Control	SDN Controller Integrity	Y.3813	6G Core Prep

📋 Field Audit Checklist (Quantum-Safe)

[ ] KM Isolation: Is the Key Manager (KM) logically and physically isolated from the user-plane traffic?
[ ] Quantum-Bit-Error-Rate (QBER): Is the QBER monitored in real-time to detect eavesdropping/intercept?
[ ] PQC Integration: For nodes without dedicated quantum fiber, is Post-Quantum Cryptography (PQC) (NIST-standardized) enforced?
[ ] Key Storage: Are symmetric keys stored in a Hardware Security Module (HSM) verified for quantum-safe access control?
[ ] Channel Resilience: Is there an automated failover to classical (ECC/RSA) links if the quantum channel is jammed/noisy?

📂 Visual Architecture

Quantum-Safe Topology: Mermaid diagram of the Quantum-Safe 6G Core.

!IMPORTANTAudit Hint: When auditing a high-security link (e.g., Command & Control), check if the Key Manager (KM) follows Y.3803 for key isolation and secure storage.

Temporal SignatureSYNC_ID: 19E40411A92

ITU-T Navigator v4.0.0

IntegritySIGNAL: SECURE