QKD Key Provisioning With Multi-Level Pool Slicing for End-to-End Security Services in Optical Networks

Quantum key distribution (QKD) provides future-proofed security based on the quantum physics. The end-to-end security services in the fields such as finance, government, and military are mainly carried by optical networks. Limited by technical and economical obstacles of QKD deployment, partially-QKD-deployed optical networks (pQKD-ONs) are much more practical. Key pooling is a technique to decouple keys from the underlying infrastructure for timely key provisioning. However, traditional QKD key provisioning (QKPR) methods are specific to QKD-deployed nodes. In this paper, we propose the pQKD-ON architecture and design the multi-level key pool slicing scheme for key management in pQKD-ONs. Then, we propose a general auxiliary-graph-based QKPR algorithm for key supply in pQKD-ONs. Based on the algorithm, we design four dynamic QKPR policies by adjusting edge weights of the auxiliary graphs including Quantum-Key-Pool-First (QKP-First), Key-Pool-Slice-First (KPS-First), Key-Availability-First (KA-First), and Quantum-Key-Pool-All (QKP-All) policies. We evaluate the performances of the QKPR policies in terms of key consumption, security level, and QKPR latency under two network topologies. Simulation results show that the KA-First policy can achieve 9.9% lower key consumption ratio than the KPS-First policy; the KPS-First policy sacrifices the security level but can achieve lower QKPR latency than the QKP-First and QKP-All policies.