The advent of quantum computing threatens classical cryptographic mechanisms, demanding new strategies for securing communication networks. Since real-world networks cannot be fully Quantum Key Distribution (QKD)-enabled due to infrastructure constraints, practical security solutions must support hybrid operation. This paper presents an adaptive security framework that enables quantum-safe communications across real-world heterogeneous networks by combining QKD and Post-Quantum Cryptography (PQC). Building upon a hierarchical key management architecture with Virtual Key Management Systems (vKMS) and a centralized Quantum Security Controller (QuSeC), the framework dynamically assigns security levels based on node capabilities. By transitioning between pure QKD, hybrid, and PQC modes, it ensures end-to-end quantum-safe protection regardless of the underlying node capabilities. The framework has been implemented and validated on a Kubernetes-based containerized testbed, demonstrating robust operation and performance across all scenarios. Results highlight its potential to support the gradual integration of quantum-safe technologies into existing infrastructures, paving the way toward fully quantum-safe communication networks.

翻译：量子计算的出现对经典密码机制构成威胁，亟需新的通信网络安全策略。由于基础设施限制，真实网络无法完全支持量子密钥分发（QKD），因此实用安全方案必须支持混合运行模式。本文提出一种自适应安全框架，通过结合QKD与后量子密码学（PQC），实现跨真实异构网络的量子安全通信。该框架基于包含虚拟密钥管理系统（vKMS）和集中式量子安全控制器（QuSeC）的分层密钥管理架构，能根据节点能力动态分配安全等级。通过在纯QKD、混合模式与PQC模式间灵活切换，该框架确保端到端的量子安全防护，且不受底层节点能力限制。该框架已在基于Kubernetes的容器化测试平台上实现并验证，在所有场景中均展现出稳健的运行性能。结果凸显了其支持量子安全技术逐步融入现有基础设施的潜力，为构建完全量子安全的通信网络铺平道路。