{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,13]],"date-time":"2026-03-13T18:00:22Z","timestamp":1773424822866,"version":"3.50.1"},"reference-count":30,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2025,3,18]],"date-time":"2025-03-18T00:00:00Z","timestamp":1742256000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Taif University"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Symmetry"],"abstract":"<jats:p>With the increasing complexity of cyber threats and the emergence of quantum computing, enhancing secure communication is essential. This study explores an effective hybrid quantum key distribution (QKD) protocol that integrates photonic and atomic systems to leverage their respective strengths. The concept of symmetry plays a crucial role in this context, as it underpins the principles of entanglement and the balance between key generation and error correction. The photonic system is used for the initial key generation, while the atomic system facilitates entanglement swapping, error correction, and privacy amplification. The comprehensive theoretical framework encompasses key components, detailed security proofs, performance metrics, and an analysis of system vulnerabilities, illustrating the resilience of the hybrid protocol against potential threats. Extensive experimental studies demonstrate that the hybrid QKD protocol seamlessly integrates photonic and atomic systems, enabling secure key distribution with minimal errors and loss rates over long distances. This combination of the two systems reveals exceptional resilience against eavesdropping, significantly improving both security and robustness compared with traditional QKD protocols. Consequently, this makes it a compelling solution for secure communication in the increasingly digital world.<\/jats:p>","DOI":"10.3390\/sym17030458","type":"journal-article","created":{"date-parts":[[2025,3,18]],"date-time":"2025-03-18T12:03:06Z","timestamp":1742299386000},"page":"458","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Enhancing Quantum Key Distribution Security Through Hybrid Protocol Integration"],"prefix":"10.3390","volume":"17","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-1418-4715","authenticated-orcid":false,"given":"Suhare","family":"Solaiman","sequence":"first","affiliation":[{"name":"Department of Computer Sciences, College of Computers and Information Technology, Taif University, P.O. Box 11099, Taif 21944, Saudi Arabia"}]}],"member":"1968","published-online":{"date-parts":[[2025,3,18]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Grimes, R.A. 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