{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,13]],"date-time":"2026-04-13T22:54:03Z","timestamp":1776120843507,"version":"3.50.1"},"reference-count":47,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2018,11,4]],"date-time":"2018-11-04T00:00:00Z","timestamp":1541289600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Continuous authentication systems for mobile devices focus on identifying users according to their behaviour patterns when they interact with mobile devices. Among the benefits provided by these systems, we highlight the enhancement of the system security, having permanently authenticated the users; and the improvement of the users\u2019 quality of experience, minimising the use of authentication credentials. Despite the benefits of these systems, they also have open challenges such as the authentication accuracy and the adaptability to new users\u2019 behaviours. Continuous authentication systems should manage these challenges without forgetting critical aspects of mobile devices such as battery consumption, computational limitations and response time. With the goal of improving these previous challenges, the main contribution of this paper is the design and implementation of an intelligent and adaptive continuous authentication system for mobile devices. The proposed system enables the real-time users\u2019 authentication by considering statistical information from applications, sensors and Machine Learning techniques based on anomaly detection. Several experiments demonstrated the accuracy, adaptability, and resources consumption of our solution. Finally, its utility is validated through the design and implementation of an online bank application as proof of concept, which allows users to perform different actions according to their authentication level.<\/jats:p>","DOI":"10.3390\/s18113769","type":"journal-article","created":{"date-parts":[[2018,11,5]],"date-time":"2018-11-05T10:43:45Z","timestamp":1541414625000},"page":"3769","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":28,"title":["Improving the Security and QoE in Mobile Devices through an Intelligent and Adaptive Continuous Authentication System"],"prefix":"10.3390","volume":"18","author":[{"given":"Jos\u00e9 Mar\u00eda","family":"Jorquera Valero","sequence":"first","affiliation":[{"name":"Department of Information and Communications Engineering (DIIC), University of Murcia, 30100 Murcia, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Pedro Miguel","family":"S\u00e1nchez S\u00e1nchez","sequence":"additional","affiliation":[{"name":"Department of Information and Communications Engineering (DIIC), University of Murcia, 30100 Murcia, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2027-4239","authenticated-orcid":false,"given":"Lorenzo","family":"Fern\u00e1ndez Maim\u00f3","sequence":"additional","affiliation":[{"name":"Department of Computer Engineering (DITEC), University of Murcia, 30100 Murcia, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Alberto","family":"Huertas Celdr\u00e1n","sequence":"additional","affiliation":[{"name":"Telecommunications Software &amp; Systems Group, Waterford Institute of Technology, Co., X91 K0EK Waterford, Ireland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Marcos","family":"Arjona Fern\u00e1ndez","sequence":"additional","affiliation":[{"name":"Innovation and Labs, ElevenPaths, Cybersecurity Unit of Telef\u00f3nica Digital Espa\u00f1a, 29071 M\u00e1laga, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sergio","family":"De Los Santos V\u00edlchez","sequence":"additional","affiliation":[{"name":"Innovation and Labs, ElevenPaths, Cybersecurity Unit of Telef\u00f3nica Digital Espa\u00f1a, 29071 M\u00e1laga, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5532-6604","authenticated-orcid":false,"given":"Gregorio","family":"Mart\u00ednez P\u00e9rez","sequence":"additional","affiliation":[{"name":"Department of Information and Communications Engineering (DIIC), University of Murcia, 30100 Murcia, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2018,11,4]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"142","DOI":"10.1016\/j.compeleceng.2014.10.018","article-title":"Multi-modal Decision Fusion for Continuous Authentication","volume":"41","author":"Fridman","year":"2015","journal-title":"Comput. 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