{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,30]],"date-time":"2026-06-30T08:48:02Z","timestamp":1782809282604,"version":"3.54.5"},"reference-count":0,"publisher":"ECMS","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2026,6,23]]},"abstract":"<jats:p>Quantum cryptography offers possibilities to distribute keys securely by relying on the principles of quantum mechanics. This paper presents repeatable simulations of two well-known quantum key distribution protocols, BB84 and E91, and examines how eavesdropping, noise, and transmission losses affect their security. The simulations are carried out using the Qiskit framework. A theoretical analysis of the expected quantum bit error rate (QBER) under ideal conditions and during an intercept\u2013resend attack is included. The Clauser\u2013Horne\u2013Shimony\u2013Holt (CHSH) parameter is also evaluated for the entanglement-based protocol. The results show error rates close to zero without attack, an increase to about 25\\% under eavesdropping, and reduced correlations in the presence of attacks or losses. For the E91 protocol, the CHSH parameter exceeds the classical bound (S &gt;2) in the entangled scenario and drops below the classical limit (S  &lt;= 2) in the attack case.<\/jats:p>","DOI":"10.7148\/2026-0345","type":"proceedings-article","created":{"date-parts":[[2026,6,30]],"date-time":"2026-06-30T08:36:46Z","timestamp":1782808606000},"page":"345-351","source":"Crossref","is-referenced-by-count":0,"title":["Quantum key distribution in simulation practice: qber and key rate in bb84 and chsh in e91"],"prefix":"10.7148","author":[{"given":"Piotre","family":"Warcholek","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Joanna","family":"Kolodziej","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Pino","family":"Caballero Gil","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"4144","published-online":{"date-parts":[[2026,6,23]]},"event":{"name":"40th ECMS International Conference on Modelling and Simulation"},"container-title":["ECMS 2026 Proceedings edited by Filippo Sanfilippo, Florenc Demrozi, Fabio Sgarbossa, Mohammad Poursina"],"original-title":[],"deposited":{"date-parts":[[2026,6,30]],"date-time":"2026-06-30T08:36:57Z","timestamp":1782808617000},"score":1,"resource":{"primary":{"URL":"http:\/\/www.scs-europe.net\/dlib\/2026\/ecms2026acceptedpapers\/0345_secmos_ecms2026_0101.pdf"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,6,23]]},"references-count":0,"URL":"https:\/\/doi.org\/10.7148\/2026-0345","relation":{},"subject":[],"published":{"date-parts":[[2026,6,23]]}}}