QuIKS: Near-Zero Latency Key Supply with Adaptive Buffering for Resource-Efficient Quantum Key Distribution Networks

TL;DR

QuIKS is a novel adaptive buffering scheme for QKD networks that achieves near-zero latency key supply with significantly reduced key resource consumption, enhancing practical deployment.

Contribution

It introduces a new analytical model and a lightweight control algorithm for ultra-low buffer size, enabling efficient, near-zero latency key supply in QKD networks.

Findings

QuIKS reduces key buffer size by over 10 times compared to existing schemes.

It achieves near-zero key supply latency in real QKD testbed experiments.

The adaptive scheme dynamically adjusts to application and network conditions.

Abstract

Quantum key distribution (QKD) networks provide information-theoretically secure keys for distant parties, emerging as a vital alternative to classical cryptography infrastructures threatened by quantum computing. In QKD networks, the immediacy of key supply service is crucial to the security and performance of applications, as their data must be encrypted before transmission. While key buffering can enable instant key supply services, existing schemes rely on heuristic solutions that incur prohibitive key resource consumption, thus significantly hindering practical deployment. To address this issue, we propose QuIKS, an instant key supply scheme based on adaptive buffering, offering the dominant advantage of near-zero key supply latency while consuming ultra-low key resources (i.e., ultra-low buffer size). Specifically, it is built upon a novel analytical model that determines the minimum buffer size required to guarantee near-zero-latency key supply performance. Guided by this model, QuIKS introduces a lightweight two-phase control algorithm that dynamically determines key relaying requests and adjusts the buffer size by probing real-time application patterns and network conditions. Experiments on a real QKD network testbed demonstrate that QuIKS achieves near-zero key supply latency while providing a more than 10-fold reduction in key buffer size compared to state-of-the-art schemes.