Fault-Tolerant Quantum Communication over r-Robust Graph Topologies under Adversarial and Noisy Conditions
Suresh Kumar Jha, Siddhanta Kumar Singh, Aditya Narayan Hati
Abstract The realization of scalable quantum communication networks faces critical challenges from decoherence, noise, and adversarial attacks. This paper presents a comprehensive framework for fault-tolerant quantum communication using \textit{r}-robust graph topologies, which ensure strong connectivity and resilience in the presence of both random failures and Byzantine adversaries. We formalize \textit{r}-robustness in single-layer and multiplex quantum networks and derive theoretical bounds on fidelity, consensus success, and error propagation. A hybrid quantum-classical protocol is proposed that leverages multi-path entanglement and quantum certificate-based identity enforcement. Extensive simulations using Qiskit and NetworkX show that \textit{r}-robust networks improve average entanglement fidelity by up to 26\%, achieve over 95\% consensus success under 30\% adversarial nodes, and exponentially suppress error rates. Compared to ring, scale-free, and random graphs, \textit{r}-robust topologies provide superior robustness with moderate resource overhead. Our results establish a graph-theoretic foundation for constructing secure, resilient, and NISQ-compatible quantum networks capable of sustaining high-performance communication in noisy and adversarial environments.
•Jan 8, 2026•0 citations