{"paper":{"title":"Long-term Performance Analysis of a Commercial QKD Device Under Real-world Deployment Conditions","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"A commercial QKD device maintains visibility above 97 percent and average QBER below 1 percent across months of continuous operation on Brazilian fiber links.","cross_cats":[],"primary_cat":"quant-ph","authors_text":"Alisson Tezzin, Gustavo M. Uhdre, Oscar Martins, Sabrina Rufo, Vitor G.A. Carneiro","submitted_at":"2026-04-17T16:54:02Z","abstract_excerpt":"Quantum key distribution (QKD) has reached a commercially viable stage, with several companies offering hardware systems designed for operational deployment. Evaluating the performance of commercial QKD devices under real-world deployment conditions is essential for users seeking to understand the practical limitations and operational reliability of these systems. In this paper, we present a long-term performance analysis of ID Quantique's Clavis XGR deployed within the Hermes Quantum Network, in Brazil. Our study provides a detailed characterization of key operational metrics, such as secret "},"claims":{"count":4,"items":[{"kind":"strongest_claim","text":"Our results demonstrate excellent overall baseline resilience, with the system maintaining visibility above 97% and QBER below 1% on average.","source":"verdict.strongest_claim","status":"machine_extracted","claim_id":"C1","attestation":"unclaimed"},{"kind":"weakest_assumption","text":"The monitored periods and two specific fiber links are representative of typical operational conditions and that no undisclosed data filtering or post-selection affected the reported averages.","source":"verdict.weakest_assumption","status":"machine_extracted","claim_id":"C2","attestation":"unclaimed"},{"kind":"one_line_summary","text":"A commercial QKD device sustained visibility above 97% and QBER below 1% over extended operation on indoor and outdoor fibers in a tropical climate.","source":"verdict.one_line_summary","status":"machine_extracted","claim_id":"C3","attestation":"unclaimed"},{"kind":"headline","text":"A commercial QKD device maintains visibility above 97 percent and average QBER below 1 percent across months of continuous operation on Brazilian fiber links.","source":"verdict.pith_extraction.headline","status":"machine_extracted","claim_id":"C4","attestation":"unclaimed"}],"snapshot_sha256":"e79d6e1e3d8a714e79321f1e923d1750d82c2e6cb86cff92d4de52a5ae88288c"},"source":{"id":"2604.16236","kind":"arxiv","version":2},"verdict":{"id":"fb423211-58b2-4505-bf4e-a6ada98aa3d3","model_set":{"reader":"grok-4.3"},"created_at":"2026-05-10T08:43:45.256187Z","strongest_claim":"Our results demonstrate excellent overall baseline resilience, with the system maintaining visibility above 97% and QBER below 1% on average.","one_line_summary":"A commercial QKD device sustained visibility above 97% and QBER below 1% over extended operation on indoor and outdoor fibers in a tropical climate.","pipeline_version":"pith-pipeline@v0.9.0","weakest_assumption":"The monitored periods and two specific fiber links are representative of typical operational conditions and that no undisclosed data filtering or post-selection affected the reported averages.","pith_extraction_headline":"A commercial QKD device maintains visibility above 97 percent and average QBER below 1 percent across months of continuous operation on Brazilian fiber links."},"integrity":{"clean":true,"summary":{"advisory":0,"critical":0,"by_detector":{},"informational":0},"endpoint":"/pith/2604.16236/integrity.json","findings":[],"available":true,"detectors_run":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938"},"references":{"count":0,"sample":[],"resolved_work":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57","internal_anchors":0},"formal_canon":{"evidence_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"author_claims":{"count":0,"strong_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"builder_version":"pith-number-builder-2026-05-17-v1"}