{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T04:01:41Z","timestamp":1760241701388,"version":"build-2065373602"},"reference-count":17,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2018,7,18]],"date-time":"2018-07-18T00:00:00Z","timestamp":1531872000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Entropy"],"abstract":"<jats:p>A semiquantum key distribution (SQKD) protocol makes it possible for a quantum party and a classical party to generate a secret shared key. However, many existing SQKD protocols are not experimentally feasible in a secure way using current technology. An experimentally feasible SQKD protocol, \u201cclassical Alice with a controllable mirror\u201d (the \u201cMirror protocol\u201d), has recently been presented and proved completely robust, but it is more complicated than other SQKD protocols. Here we prove a simpler variant of the Mirror protocol (the \u201csimplified Mirror protocol\u201d) to be completely non-robust by presenting two possible attacks against it. Our results show that the complexity of the Mirror protocol is at least partly necessary for achieving robustness.<\/jats:p>","DOI":"10.3390\/e20070536","type":"journal-article","created":{"date-parts":[[2018,7,19]],"date-time":"2018-07-19T03:50:43Z","timestamp":1531972243000},"page":"536","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":16,"title":["Attacks against a Simplified Experimentally Feasible Semiquantum Key Distribution Protocol"],"prefix":"10.3390","volume":"20","author":[{"given":"Michel","family":"Boyer","sequence":"first","affiliation":[{"name":"D\u00e9partement d\u2019Informatique et de Recherche Op\u00e9rationnelle (DIRO), Universit\u00e9 de Montr\u00e9al, Montr\u00e9al, QC H3C 3J7, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1579-0095","authenticated-orcid":false,"given":"Rotem","family":"Liss","sequence":"additional","affiliation":[{"name":"Computer Science Department, Technion, Haifa 3200003, Israel"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Tal","family":"Mor","sequence":"additional","affiliation":[{"name":"Computer Science Department, Technion, Haifa 3200003, Israel"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2018,7,18]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"140501","DOI":"10.1103\/PhysRevLett.99.140501","article-title":"Quantum Key Distribution with Classical Bob","volume":"99","author":"Boyer","year":"2007","journal-title":"Phys. Rev. Lett."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"032341","DOI":"10.1103\/PhysRevA.79.032341","article-title":"Semiquantum key distribution","volume":"79","author":"Boyer","year":"2009","journal-title":"Phys. Rev. A"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"052312","DOI":"10.1103\/PhysRevA.79.052312","article-title":"Semiquantum-key distribution using less than four quantum states","volume":"79","author":"Zou","year":"2009","journal-title":"Phys. Rev. A"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"046301","DOI":"10.1103\/PhysRevA.83.046301","article-title":"Comment on \u201cSemiquantum-key distribution using less than four quantum states\u201d","volume":"83","author":"Boyer","year":"2011","journal-title":"Phys. Rev. A"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"1195","DOI":"10.1142\/S0219749908004353","article-title":"Quantum key distribution with classical Alice","volume":"06","author":"Lu","year":"2008","journal-title":"Int. J. Quantum Inf."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"1350005","DOI":"10.1142\/S0219749913500056","article-title":"Quantum key distribution with limited classical Bob","volume":"11","author":"Sun","year":"2013","journal-title":"Int. J. Quantum Inf."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"1457","DOI":"10.1007\/s11128-014-0740-z","article-title":"Authenticated semi-quantum key distribution protocol using Bell states","volume":"13","author":"Yu","year":"2014","journal-title":"Quantum Inf. Process."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"032323","DOI":"10.1103\/PhysRevA.91.032323","article-title":"Mediated semiquantum key distribution","volume":"91","author":"Krawec","year":"2015","journal-title":"Phys. Rev. A"},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"2981","DOI":"10.1007\/s11128-015-1015-z","article-title":"Semiquantum key distribution without invoking the classical party\u2019s measurement capability","volume":"14","author":"Zou","year":"2015","journal-title":"Quantum Inf. Process."},{"key":"ref_10","doi-asserted-by":"crossref","unstructured":"Krawec, W.O. (2015, January 14\u201319). Security proof of a semi-quantum key distribution protocol. Proceedings of the 2015 IEEE International Symposium on Information Theory (ISIT), Hong Kong, China.","DOI":"10.1109\/ISIT.2015.7282542"},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"2067","DOI":"10.1007\/s11128-016-1266-3","article-title":"Security of a semi-quantum protocol where reflections contribute to the secret key","volume":"15","author":"Krawec","year":"2016","journal-title":"Quantum Inf. Process."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"135","DOI":"10.1007\/s11128-018-1904-z","article-title":"Security of a single-state semi-quantum key distribution protocol","volume":"17","author":"Zhang","year":"2018","journal-title":"Quantum Inf. Process."},{"key":"ref_13","first-page":"1066009","article-title":"Practical security of semi-quantum key distribution","volume":"Volumme 10660","author":"Donkor","year":"2018","journal-title":"Proceedings of SPIE, Quantum Information Science, Sensing, and Computation X"},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"098901","DOI":"10.1103\/PhysRevLett.102.098901","article-title":"Comment on \u201cQuantum Key Distribution with Classical Bob\u201d","volume":"102","author":"Tan","year":"2009","journal-title":"Phys. Rev. Lett."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"098902","DOI":"10.1103\/PhysRevLett.102.098902","article-title":"Boyer, Kenigsberg, and Mor Reply","volume":"102","author":"Boyer","year":"2009","journal-title":"Phys. Rev. Lett."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"062335","DOI":"10.1103\/PhysRevA.96.062335","article-title":"Experimentally feasible protocol for semiquantum key distribution","volume":"96","author":"Boyer","year":"2017","journal-title":"Phys. Rev. A"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"1330","DOI":"10.1103\/PhysRevLett.85.1330","article-title":"Limitations on Practical Quantum Cryptography","volume":"85","author":"Brassard","year":"2000","journal-title":"Phys. Rev. Lett."}],"container-title":["Entropy"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1099-4300\/20\/7\/536\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T15:12:49Z","timestamp":1760195569000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1099-4300\/20\/7\/536"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2018,7,18]]},"references-count":17,"journal-issue":{"issue":"7","published-online":{"date-parts":[[2018,7]]}},"alternative-id":["e20070536"],"URL":"https:\/\/doi.org\/10.3390\/e20070536","relation":{},"ISSN":["1099-4300"],"issn-type":[{"type":"electronic","value":"1099-4300"}],"subject":[],"published":{"date-parts":[[2018,7,18]]}}}