Design and Performance Evaluation of a Hybrid Classical–Post-Quantum Cryptographic Architecture for Secure Cloud Communication

Abstract

The emergence of quantum computing has created significant challenges for conventional public-key cryptographic systems that currently secure cloud communication. Hybrid classical–post-quantum cryptographic architectures have therefore gained attention as a practical approach for maintaining compatibility with existing infrastructures while enhancing resistance against future quantum-enabled attacks. This study evaluated the communication characteristics of a hybrid cryptographic architecture using the CIC-PQC-OAV-2025 dataset comprising 40,010 secure communication sessions representing classical, post-quantum, hybrid, adversarial, and misconfigured operational scenarios. A quantitative comparative approach was adopted to examine communication overhead, session efficiency, protocol behaviour, and security-related characteristics. Descriptive statistical analysis was performed using Python to evaluate communication features, operational configurations, anomaly distributions, and correlations among key performance variables. The findings revealed considerable variation in transmitted bytes, flow duration, packet sizes, and record lengths across different cryptographic deployments, demonstrating the dataset's capability to support comprehensive performance evaluation. The operational distribution confirmed substantial representation of classical and post-quantum configurations together with dedicated hybrid communication scenarios, while anomaly-labelled sessions enabled simultaneous assessment of communication efficiency and security robustness. Correlation analysis further identified meaningful relationships among major communication variables influencing protocol performance. Overall, the results indicate that hybrid classical–post-quantum cryptographic architectures provide a practical transition strategy toward quantum-safe cloud communication by balancing operational compatibility, communication performance, and enhanced security. The study offers a useful analytical foundation for future implementation and validation of hybrid cryptographic systems in enterprise cloud environments.