Fault-Tolerant Quantum Communication over r-Robust Graph Topologies under Adversarial and Noisy Conditions

Suresh Kumar Jha, Siddhanta Kumar Singh, Aditya Narayan Hati

Published Jan 8, 2026• 0 citations

Abstract

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.

DOI: 10.21203/rs.3.rs-7262145/v1

Related papers

Strategic Evolution of Quantum Communication Leveraging Non-Local Topological Robustness and Dynamic Protocols

Sreeja Poduri, Lalit Kovvuri, Lavanya Addepalli +2 more

In this paper we propose a new Topological Quantum Network (TQN) for ultra-secure communication that prevents these limitations of conventional networks in dynamic and noisy environments. The methodology proposed here encodes and transmits information using topological quantum states which can survive noise from the environment and physical disruptions. We integrate fault tolerant quantum repeaters for reliable long-distance communication and an adaptive error correction protocol to dynamically optimize the performance depending on the real time noise profiles. The effectiveness of the network is validated through simulations over urban, underwater, and space-based scenarios that show reductions in error rate as well as improvements in communication fidelity and cost efficiency. This work introduces a scalable and resilient solution to secure quantum communication and toward the deployment in global and interplanetary networks. Finally, future directions of the research are discussed to push practical implementations a step further, including experimental validation and hardware advancements.

CRC Press eBooksSep 10, 20260 citations

Distributed Consensus with Quantum Byzantine Fault Tolerance

Jincheng Zhang

This paper presents a novel approach to distributed consensus protocols leveraging quantum entanglement and Byzantine fault tolerance. The core claim is that quantum entanglement can provide secure and efficient agreement among nodes even in the presence of malicious actors. We propose a mechanism that utilizes quantum key distribution (QKD) to establish shared entanglement between participating nodes. Subsequent quantum measurements identify faulty nodes, informing a robust consensus algorithm built upon majority voting and entanglement-based error correction. The potential advantages of this combined approach – enhanced security and efficiency compared to traditional classical methods – are explored. The research addresses the critical challenge of achieving reliable consensus in distributed systems susceptible to Byzantine attacks. This work introduces a new paradigm for consensus, potentially leading to more resilient and secure distributed applications.

Aug 29, 20260 citations

Quantum Entanglement-Based Information Encoding and Topological Network Routing

Jincheng Zhang

This paper proposes a novel approach to information transmission leveraging the unique properties of quantum entanglement within a topological network architecture. The core idea is to construct a network of entangled nodes, enabling efficient and robust information routing. We introduce a framework for encoding information using entangled states and propose a routing protocol based on entanglement swapping and entanglement protection techniques to mitigate the effects of node failures, a significant limitation in conventional quantum communication. The resulting system offers the potential to surpass the fundamental limits imposed by classical physics in terms of information transfer rates and resilience. The system's performance is analyzed using key metrics, demonstrating its capability for high-capacity, fault-tolerant communication. This research contributes to the development of advanced quantum communication networks with enhanced security and scalability.

Sep 5, 20260 citations

Quantum Network Science: Linking Graph Structure to Entanglement Performance

Rawan AlMakinah, Muhammed Abdullah Canbaz

Quantum communication networks—the substrate of a future quantum Internet—demand analytical tools that account for entanglement, fidelity, and quantum-specific constraints absent from classical models. In this paper, we introduce the Quantum Network Science (QNS) framework that adapts core network metrics to the quantum setting through fidelity-, success-probability-, and capacity-aware weighting. We formalize centrality (including Quantum PageRank and continuous-time quantum-walk variants), community structure on entanglement graphs, and robustness/percolation with fidelity thresholds. The framework is validated via analytic motifs and controlled simulations on Erdős–Rényi, scale-free, and small-world topologies, as well as satellite-assisted versus fiber-only designs. Our results show that (i) fidelity weighting reorders structural importance and can reconnect networks that appear fragmented classically; (ii) heavy-tailed degree patterns improve tolerance to random failures but heighten vulnerability to targeted hub attacks; (iii) small-world shortcuts induced by long-range quantum links shrink path lengths; and (iv) overlapping “connected components” emerge from entanglement swapping, motivating revised connectivity baselines. We also discuss design implications—degree caps and hub hardening, link-type diversity, multipath routing, and buffering policies—and outline extensions to temporal and multilayer modeling that couple the quantum plane with its classical control layer. QNS thus offers a principled, measurement-oriented foundation for analyzing, comparing, and engineering resilient, high-capacity quantum networks.

Proceedings of the AAAI Symposium SeriesNov 23, 20250 citations

Distributed Consensus Algorithms with Byzantine Fault Tolerance via Quantum Entanglement

Jincheng Zhang

This paper proposes a novel distributed consensus algorithm utilizing quantum entanglement to achieve Byzantine fault tolerance. Traditional consensus algorithms struggle to guarantee correctness in the face of malicious actors (Byzantine faults) where nodes can arbitrarily deviate from the honest majority. This work introduces a protocol that leverages the unique properties of quantum entanglement to establish correlated states between nodes, enabling the detection and mitigation of these malicious behaviors without relying on trusted third parties or computationally intensive verification processes. The core claim is that quantum entanglement provides a provably secure and efficient mechanism for distributed consensus, offering superior resilience compared to classical approaches. The algorithm is formally described, and key mathematical components, including state transformations and probability calculations, are presented. The theoretical analysis demonstrates the algorithm's ability to converge to a correct consensus state even when a significant fraction of nodes are faulty. The use of entanglement fundamentally alters the Byzantine fault tolerance landscape, offering a pathway towards more robust and secure distributed systems.

Sep 3, 20260 citations

Multi-path Security in Quantum Networks with Trusted Nodes

Muhammad Kumail Haider, Aeysha Khalique

Quantum communication networks promise information-theoretic security but this security collapses if intermediate relay nodes are compromised, a risk that grows sharply when compromised nodes cannot be identified. We address this twofold: first, we show that multi-path routing provides quantifiable protection against unidentified compromised nodes. Second, we provide a comprehensive statistical and graph-theoretic analysis of network and node security under compromise, covering full and partial node compromise, optimal placement of additional edges via an iterative method, and comparative hacking-probability analysis across network topologies. Together, these results identify the topology and multi-path routing strategy that most improves security for a given network. We apply this framework to quantum key distribution across multiple network topologies, demonstrating a scalable route to secure, reliable quantum communication under realistic, unidentified adversarial threats, without relying on quantum memory.

quant-pharXiv:2610.26120Oct 20, 20260 citations