Topology-Hiding Connectivity-Assurance for QKD Inter-Networking

Computer Science > Cryptography and Security [Submitted on 2 Apr 2026] Topology-Hiding Connectivity-Assurance for QKD Inter-Networking Margherita Cozzolino, Stephan Krenn, Thomas Lorünser While QKD ensures information-theoretic security at the link level, real-world deployments depend on trusted repeaters, creating potential vulnerabilities. In this paper, we thus introduce a topology-hiding connectivity assurance protocol to enhance trust in quantum key distribution (QKD) network infrastructures. Our protocol allows network providers to jointly prove the existence of a secure connection between endpoints without revealing internal topology details. By extending graph-signature techniques to support multi-graphs and hidden endpoints, we enable zero-knowledge proofs of connectivity that ensure both soundness and topology hiding. We further discuss how our approach can certify, e.g., multiple disjoint paths, supporting multi-path QKD scenarios. This work bridges cryptographic assurance methods with the operational requirements of QKD networks, promoting verifiable and privacy-preserving inter-network connectivity. Subjects: Cryptography and Security (cs.CR); Quantum Physics (quant-ph) Cite as: arXiv:2604.01876 [cs.CR]   (or arXiv:2604.01876v1 [cs.CR] for this version)   https://doi.org/10.48550/arXiv.2604.01876 Focus to learn more Submission history From: Stephan Krenn [view email] [v1] Thu, 2 Apr 2026 10:30:43 UTC (125 KB) Access Paper: view license Current browse context: cs.CR < prev   |   next > new | recent | 2026-04 Change to browse by: cs quant-ph References & Citations INSPIRE HEP NASA ADS Google Scholar Semantic Scholar Export BibTeX Citation Bookmark Bibliographic Tools Bibliographic and Citation Tools Bibliographic Explorer Toggle Bibliographic Explorer (What is the Explorer?) Connected Papers Toggle Connected Papers (What is Connected Papers?) Litmaps Toggle Litmaps (What is Litmaps?) scite.ai Toggle scite Smart Citations (What are Smart Citations?) Code, Data, Media Demos Related Papers About arXivLabs Which authors of this paper are endorsers? | Disable MathJax (What is MathJax?)