{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,2]],"date-time":"2026-04-02T18:35:10Z","timestamp":1775154910391,"version":"3.50.1"},"reference-count":32,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2022,6,30]],"date-time":"2022-06-30T00:00:00Z","timestamp":1656547200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["62071151"],"award-info":[{"award-number":["62071151"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Entropy"],"abstract":"<jats:p>Quantum key distribution (QKD) can provide point-to-point information-theoretic secure key services for two connected users. In fact, the development of QKD networks needs more focus from the scientific community in order to broaden the service scale of QKD technology to deliver end-to-end secure key services. Of course, some recent efforts have been made to develop secure communication protocols based on QKD. However, due to the limited key generation capability of QKD devices, high quantum secure key utilization is the major concern for QKD networks. Since traditional routing techniques do not account for the state of quantum secure keys on links, applying them in QKD networks directly will result in underutilization of quantum secure keys. Therefore, an efficient routing protocol for QKD networks, especially for large-scale QKD networks, is desperately needed. In this study, an efficient routing protocol based on optimized link-state routing, namely QOLSR, is proposed for QKD networks. QOLSR considerably improves quantum key utilization in QKD networks through link-state awareness and path optimization. Simulation results demonstrate the validity and efficiency of the proposed QOLSR routing protocol. Most importantly, with the growth of communication traffic, the benefit becomes even more apparent.<\/jats:p>","DOI":"10.3390\/e24070911","type":"journal-article","created":{"date-parts":[[2022,6,30]],"date-time":"2022-06-30T20:53:02Z","timestamp":1656622382000},"page":"911","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":17,"title":["An Efficient Routing Protocol for Quantum Key Distribution Networks"],"prefix":"10.3390","volume":"24","author":[{"given":"Jiameng","family":"Yao","sequence":"first","affiliation":[{"name":"Department of Computer Science and Technology, Harbin Institute of Technology, Harbin 150080, China"}]},{"given":"Yaxing","family":"Wang","sequence":"additional","affiliation":[{"name":"Department of Computer Science and Technology, Harbin Institute of Technology, Harbin 150080, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8627-4066","authenticated-orcid":false,"given":"Qiong","family":"Li","sequence":"additional","affiliation":[{"name":"Department of Computer Science and Technology, Harbin Institute of Technology, Harbin 150080, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2783-821X","authenticated-orcid":false,"given":"Haokun","family":"Mao","sequence":"additional","affiliation":[{"name":"Department of Computer Science and Technology, Harbin Institute of Technology, Harbin 150080, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5068-2033","authenticated-orcid":false,"given":"Ahmed A. Abd","family":"El-Latif","sequence":"additional","affiliation":[{"name":"EIAS Data Science Lab, College of Computer and Information Sciences, Prince Sultan University, Riyadh 11586, Saudi Arabia"},{"name":"Department of Mathematics and Computer Science, Faculty of Science, Menoufia University, Shibin El Kom 32511, Egypt"}]},{"given":"Nan","family":"Chen","sequence":"additional","affiliation":[{"name":"School of Foreign Languages, Harbin Institute of Technology, Harbin 150080, China"}]}],"member":"1968","published-online":{"date-parts":[[2022,6,30]]},"reference":[{"key":"ref_1","unstructured":"Fl\u00fcgge, S. (2012). Practical Quantum Mechanics, Springer."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"172","DOI":"10.1007\/BF01397280","article-title":"Uber den anschaulichen inhalt der quantentheoretischen kinematik und mechanik","volume":"43","author":"Heisenberg","year":"1927","journal-title":"Z. 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