Performance Evaluation and Security Analysis of Hybrid Classical-Quantum Cryptographic Schemes for Future-Proof Network Security

Quantum computers are approaching rapidly, and they act as a significant threat to the security systems we use today, such as RSA and Elliptic Curve Cryptography (ECC). These conventional systems can be easily broken by new quantum algorithms. To fix this problem and bridge the gap between current security and future protection, this paper builds and tests a "hybrid" cryptographic system. We combined a standard method called X25519 with a new Post-Quantum Cryptography (PQC) method called ML-KEM (Kyber-768). We tested this system on a computer running WSL2-Ubuntu using the Open Quantum Safe (OQS) library. In this study, we did not just check the speed; we also performed a detailed statistical analysis, checked resource usage, and provided a security proof. Our results show that the system is very fast (taking only about 0.10 ms) and does not slow down the network. This proves that our hybrid system is practical and ready to use for secure communication in real-time.