K. Sivasankar rao, M. Swagath Kumar, T. Shasi Kiran, R. Shanmuka Srinivas, Ms. D. Sasikala
Abstract
The advancement of quantum computing presents significant risks to conventional cryptographic systems that secure modern communication networks. This paper proposes an Adaptive Quantum–Classical Trust Communication System (AQCTCS), a hybrid secure messaging framework designed to enhance resilience against both classical and quantum threats. The system integrates three security layers: AES-256 for classical encryption, Post-Quantum Cryptography (PQC) for quantum-resistant protection, and a BB84-based Quantum Key Distribution (QKD) simulation for high-risk scenarios. A Trust Engine continuously evaluates security indicators, including anomaly detection parameters and Quantum Bit Error Rate (QBER), to compute a dynamic trust score. Based on this score, an Adaptive Security Controller automatically selects the appropriate encryption mode, balancing performance and security. The platform is implemented as a web application using React for the frontend, FastAPI for backend services, and Qiskit for QKD simulation. AQCTCS demonstrates an adaptive, scalable, and future-ready communication architecture suitable for post-quantum environments.
This paper presented AQCTCS, an Adaptive Quantum–Classical Trust-Based Secure Communication System that addresses the dual challenge of securing communications against both contemporary classical threats and emerging quantum computing capabilities. By integrating AES-256, PQC algorithms, and BB84-based QKD simulation within a unified adaptive framework governed by a dynamic Trust Engine, AQCTCS achieves context-sensitive cryptographic selection without manual intervention.
The system’s architecture — comprising modular authentication, trust evaluation, adaptive encryption, real-time messaging, and key management components — demonstrates engineering rigor and deployment feasibility through a fully functional web application built with React and FastAPI. Experimental evaluation confirms that automatic mode switching based on trust score thresholds operates correctly and that the system maintains usability throughout security-level transitions.
AQCTCS establishes a practical foundation for post-quantum secure communication architectures. Future work will focus on integrating certified PQC libraries, exploring hardware QKD interfaces, implementing asynchronous agent processing, and validating the system under high-concurrency production workloads.
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How to Cite This Paper
K. Sivasankar rao, M. Swagath Kumar, T. Shasi Kiran, R. Shanmuka Srinivas, Ms. D. Sasikala (2026). AQCTCS: An Adaptive Quantum–Classical Trust-Based Secure Communication System. International Journal of Computer Techniques, 13(3). ISSN: 2394-2231.
