Secure Multi-Party Computation using Paillier HE and Simulated BBM92 QKD: A Hybrid Quantum-Classical Approach
Kartick S. Rajen, Debarupa Mandal, Malavika Krishnamoorthy Gayathri
Secure Multi-Party Computation (MPC) facilitates cooperative computation on confidential data. Homomorphic Encryption (HE) offers primitives to compute on encrypted data, but protecting the communication channel with classical key exchange is increasingly exposed to quantum attackers. This work outlines a hybrid model where Paillier HE supports secure additive aggregation, while BBM92 QKD simulation generates quantum-resistant keys for AES-GCM, which in turn protects inter-party communication of HE ciphertexts. The model takes advantage of Paillier HE for secure additive aggregation and simulated BBM92 QKD protocol for generating information-theoretically secure symmetric keys, as opposed to keys obtained from traditional protocols such as Diffie-Hellman. These keys protect the exchange of intermediate homomorphically encrypted values among parties with AES-GCM. We outline the system architecture, Python library-based implementation (Qiskit, phe, cryptography), and simulation results proving the feasibility and improved security against quantum eavesdropping over a fully classical solution. The framework efficiently calculates aggregate sums while maintaining input confidentiality and guarantees communication security that withstands simulated eavesdropping attacks on the quantum channel.
International Conference on Next Generation of Green Information and Emerging Technologies (GIET)•Aug 8, 2025•1 citation