{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T02:12:08Z","timestamp":1760235128271,"version":"build-2065373602"},"reference-count":28,"publisher":"MDPI AG","issue":"15","license":[{"start":{"date-parts":[[2021,7,30]],"date-time":"2021-07-30T00:00:00Z","timestamp":1627603200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003407","name":"Ministero dell\u2019Istruzione, dell\u2019Universit\u00e0 e della Ricerca","doi-asserted-by":"publisher","award":["Departments of Excellence (Law 232\/2016)"],"award-info":[{"award-number":["Departments of Excellence (Law 232\/2016)"]}],"id":[{"id":"10.13039\/501100003407","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001659","name":"Deutsche Forschungsgemeinschaft","doi-asserted-by":"publisher","award":["Germany\u2019s Excellence Strategy - EXC 2092 CASA \u2013 390781972."],"award-info":[{"award-number":["Germany\u2019s Excellence Strategy - EXC 2092 CASA \u2013 390781972."]}],"id":[{"id":"10.13039\/501100001659","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>The fifth generation (5G) of cellular networks improves the precision of user localization and provides the means to disclose location information to over-the-top (OTT) service providers. The network data analytics function (NWDAF) can further elaborate this information at an aggregated level using artificial intelligence techniques. These powerful features may lead to the improper use of user location information by mobile network operators (MNOs) and OTT service providers. Moreover, vulnerabilities at various layers may also leak user location information to eavesdroppers. Hence, the privacy of users is likely at risk, as location is part of their sensitive data. In this paper, we first go through the evolution of localization in cellular networks and investigate their effects on location privacy. Then, we propose a location-privacy-preserving integrated solution comprising virtual private mobile networks, an independent authentication and billing authority, and functions to protect wireless signals against location information leakage. Moreover, we advocate the continuous and detailed control of localization services by the user.<\/jats:p>","DOI":"10.3390\/s21155176","type":"journal-article","created":{"date-parts":[[2021,8,1]],"date-time":"2021-08-01T21:44:32Z","timestamp":1627854272000},"page":"5176","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":17,"title":["Location-Privacy Leakage and Integrated Solutions for 5G Cellular Networks and Beyond"],"prefix":"10.3390","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-3253-6793","authenticated-orcid":false,"given":"Stefano","family":"Tomasin","sequence":"first","affiliation":[{"name":"Department of Information Engineering, University of Padova, 35100 Padova, Italy"},{"name":"CNIT, the National Inter-University Consortium for Telecommunications, 43124 Parma, Italy"}]},{"given":"Marco","family":"Centenaro","sequence":"additional","affiliation":[{"name":"Department of Information Engineering, University of Padova, 35100 Padova, Italy"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2494-6872","authenticated-orcid":false,"given":"Gonzalo","family":"Seco-Granados","sequence":"additional","affiliation":[{"name":"Department Telecommunications and Systems Engineering, Universitat Aut\u00f2noma de Barcelona, Bellaterra, 08193 Barcelona, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4408-3306","authenticated-orcid":false,"given":"Stefan","family":"Roth","sequence":"additional","affiliation":[{"name":"Fakult\u00e4t f\u00fcr Elektrotechnik und Informationstechnik, Ruhr University Bochum, Digitale Kommunikationssysteme, 44801 Bochm, Germany"}]},{"given":"Aydin","family":"Sezgin","sequence":"additional","affiliation":[{"name":"Fakult\u00e4t f\u00fcr Elektrotechnik und Informationstechnik, Ruhr University Bochum, Digitale Kommunikationssysteme, 44801 Bochm, Germany"}]}],"member":"1968","published-online":{"date-parts":[[2021,7,30]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"26902","DOI":"10.1109\/ACCESS.2021.3053486","article-title":"Convergent Communication, Sensing and Localization in 6G Systems: An Overview of Technologies, Opportunities and Challenges","volume":"9","author":"Belot","year":"2021","journal-title":"IEEE Access"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1973","DOI":"10.1007\/s11277-017-4284-2","article-title":"An Exploration to Location Based Service and Its Privacy Preserving Techniques: A Survey","volume":"96","author":"Gupta","year":"2017","journal-title":"Wirel. Pers. Commun."},{"key":"ref_3","unstructured":"Schmitt, P., and Raghavan, B. (2020). Pretty Good Phone Privacy. arXiv."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"1604","DOI":"10.1109\/LCOMM.2018.2843334","article-title":"Identifying the Fake Base Station: A Location Based Approach","volume":"22","author":"Huang","year":"2018","journal-title":"IEEE Commun. Lett."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"58","DOI":"10.1109\/MVT.2020.2979261","article-title":"5G Wireless Security and Privacy: Architecture and Flexible Mechanisms","volume":"15","author":"Fang","year":"2020","journal-title":"IEEE Veh. Technol. Mag."},{"key":"ref_6","doi-asserted-by":"crossref","unstructured":"Li, F., Chen, Y., Niu, B., He, Y., Geng, K., and Cao, J. (2018, January 9\u201313). Achieving Personalized k-Anonymity against Long-Term Observation in Location-Based Services. Proceedings of the IEEE Global Communications Conference (GLOBECOM), Abu Dhabi, United Arab Emirates.","DOI":"10.1109\/GLOCOM.2018.8647719"},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"3628","DOI":"10.1109\/TII.2017.2773646","article-title":"Location Privacy Protection Based on Differential Privacy Strategy for Big Data in Industrial Internet of Things","volume":"14","author":"Yin","year":"2018","journal-title":"IEEE Trans. Ind. Inform."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"13466","DOI":"10.1109\/ACCESS.2018.2805464","article-title":"Cognitive Approach for Location Privacy Protection","volume":"6","author":"Han","year":"2018","journal-title":"IEEE Access"},{"key":"ref_9","unstructured":"Beresford, A., and Stajano, F. (2004, January 14\u201317). Mix zones: User privacy in location-aware services. Proceedings of the IEEE Annual Conference on Pervasive Computing and Communications Workshops, Orlando, FL, USA."},{"key":"ref_10","doi-asserted-by":"crossref","unstructured":"Qiu, Y., Liu, Y., Li, X., and Chen, J. (2020). A Novel Location Privacy-Preserving Approach Based on Blockchain. Sensors, 20.","DOI":"10.3390\/s20123519"},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1007\/s11432-019-2834-x","article-title":"Generative adversarial networks enhanced location privacy in 5G networks","volume":"63","author":"Qu","year":"2020","journal-title":"Sci. China Inf. Sci."},{"key":"ref_12","doi-asserted-by":"crossref","unstructured":"Kohls, K., Rupprecht, D., Holz, T., and P\u00f6pper, C. (2019, January 15\u201317). Lost Traffic Encryption: Fingerprinting LTE\/4G Traffic on Layer Two. Proceedings of the 12th Conference Security Privacy Wireless Mobile Networks, Miami, FL, USA.","DOI":"10.1145\/3317549.3323416"},{"key":"ref_13","doi-asserted-by":"crossref","unstructured":"Hong, B., Bae, S., and Kim, Y. (2018, January 18\u201321). GUTI Reallocation Demystified: Cellular Location Tracking with Changing Temporary Identifier. Proceedings of the NDSS Symposium 2018, San Diego, CA, USA.","DOI":"10.14722\/ndss.2018.23349"},{"key":"ref_14","doi-asserted-by":"crossref","unstructured":"Sung, K., Levine, B., and Zheleva, M. (2020). Protecting Location Privacy from Untrusted Wireless Service Providers, Association for Computing Machinery.","DOI":"10.1145\/3395351.3399369"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"1124","DOI":"10.1109\/COMST.2017.2785181","article-title":"Survey of Cellular Mobile Radio Localization Methods: From 1G to 5G","volume":"20","author":"Raulefs","year":"2018","journal-title":"IEEE Commun. Surv. Tutor."},{"key":"ref_16","unstructured":"Witrisal, K., Ant\u00f3n-Haro, C., del Peral-Rosado, J.A., and Seco-Granados, G. (2018). Whitepaper on New Localization Methods for 5G Wireless Systems and the Internet-of-Things, COST Action CA15104; IRACON."},{"key":"ref_17","unstructured":"(2021, June 01). Stage 2 Functional Specification of User Equipment (UE) Positioning in NG-RAN (Release 16). Available online: https:\/\/portal.3gpp.org\/desktopmodules\/Specifications\/SpecificationDetails.aspx?specificationId=3310."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"3929","DOI":"10.1109\/JSYST.2019.2903278","article-title":"Passive Localization of Standard WiFi Devices","volume":"13","author":"Li","year":"2019","journal-title":"IEEE Syst. J."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"4100","DOI":"10.1109\/TWC.2021.3055851","article-title":"Localization Attack by Precoder Feedback Overhearing in 5G Networks and Countermeasures","volume":"20","author":"Roth","year":"2021","journal-title":"IEEE Trans. Wireless Commun."},{"key":"ref_20","unstructured":"(2021, July 28). 5G System (5GS) Location Services (LCS); Stage 2; (Release 16). Available online: https:\/\/www.etsi.org\/deliver\/etsi_ts\/123200_123299\/123273\/16.04.00_60\/ts_123273v160400p.pdf."},{"key":"ref_21","unstructured":"(2021, June 01). System architecture for the 5G System (5GS); Stage 2; (Release 16), 3GPP Technical Specification TS23.501. Available online: https:\/\/portal.3gpp.org\/desktopmodules\/Specifications\/SpecificationDetails.aspx?specificationId=3144."},{"key":"ref_22","unstructured":"(2021, July 28). Combain. Available online: https:\/\/combain.com\/."},{"key":"ref_23","unstructured":"(2021, July 28). LocationAPI. Available online: https:\/\/locationapi.org\/coverage."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"19","DOI":"10.1109\/MCOM.2015.7355561","article-title":"To avoid or not to avoid CSI leakage in physical layer secret communication systems","volume":"53","author":"Liu","year":"2015","journal-title":"IEEE Commun. Mag."},{"key":"ref_25","unstructured":"(2021, July 28). Privacy changes in Android 10. Available online: https:\/\/developer.android.com\/about\/versions\/10\/privacy\/changes."},{"key":"ref_26","doi-asserted-by":"crossref","unstructured":"Vegh, L. (2018, January 14\u201316). A Survey of Privacy and Security Issues for the Internet of Things in the GDPR Era. Proceedings of the 2018 International Conference on Communications (COMM), Bucharest, Romania.","DOI":"10.1109\/ICComm.2018.8484769"},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"2692","DOI":"10.1109\/LCOMM.2020.3018165","article-title":"Location-Privacy-Preserving Technique for 5G mmWave Devices","volume":"24","author":"Checa","year":"2020","journal-title":"IEEE Commun. Lett."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"1876","DOI":"10.1109\/TNET.2017.2663524","article-title":"Analytical Modeling of Multipath TCP Over Last-Mile Wireless","volume":"25","author":"Pokhrel","year":"2017","journal-title":"IEEE\/ACM Trans. Netw."}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/21\/15\/5176\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T06:37:25Z","timestamp":1760164645000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/21\/15\/5176"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2021,7,30]]},"references-count":28,"journal-issue":{"issue":"15","published-online":{"date-parts":[[2021,8]]}},"alternative-id":["s21155176"],"URL":"https:\/\/doi.org\/10.3390\/s21155176","relation":{},"ISSN":["1424-8220"],"issn-type":[{"type":"electronic","value":"1424-8220"}],"subject":[],"published":{"date-parts":[[2021,7,30]]}}}