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Data"],"published-print":{"date-parts":[[2018,12,31]]},"abstract":"<jats:p>The increased use of location-aware devices, such as smartphones, generates a large amount of trajectory data. These data can be useful in several domains, like marketing, path modeling, localization of an epidemic focus, and so on. Nevertheless, since trajectory information contains personal mobility data, improper use or publication of trajectory data can threaten users\u2019 privacy. It may reveal sensitive details like habits of behavior, religious beliefs, and sexual preferences. Therefore, many users might be unwilling to share their trajectory data without a previous anonymization process. Currently, several proposals to address this problem can be found in the literature. These solutions focus on anonymizing data before its publication, i.e., when they are already stored in the server database. Nevertheless, we argue that this approach gives the user no control about the information she shares. For this reason, we propose anonymizing data in the users\u2019 mobile devices, before they are sent to a third party. This article extends our previous work which was, to the best of our knowledge, the first one to anonymize data at the client side, allowing users to select the amount and accuracy of shared data. In this article, we describe an improved version of the protocol, and we include the implementation together with an analysis of the results obtained after the simulation with real trajectory data.<\/jats:p>","DOI":"10.1145\/3233185","type":"journal-article","created":{"date-parts":[[2018,8,30]],"date-time":"2018-08-30T13:45:11Z","timestamp":1535636711000},"page":"1-27","update-policy":"https:\/\/doi.org\/10.1145\/crossmark-policy","source":"Crossref","is-referenced-by-count":4,"title":["Protecting Privacy in Trajectories with a User-Centric Approach"],"prefix":"10.1145","volume":"12","author":[{"given":"Cristina","family":"Romero-Tris","sequence":"first","affiliation":[{"name":"Internet Interdisciplinary Institute (IN3), Universitat Oberta de Catalunya (UOC), CYBERCAT-Center for Cybersecurity Research of Catalonia"}]},{"given":"David","family":"Meg\u00edas","sequence":"additional","affiliation":[{"name":"Internet Interdisciplinary Institute (IN3), Universitat Oberta de Catalunya (UOC), CYBERCAT-Center for Cybersecurity Research of Catalonia"}]}],"member":"320","published-online":{"date-parts":[[2018,8,28]]},"reference":[{"key":"e_1_2_1_1_1","series-title":"Lecture Notes in Computer Science","volume-title":"Advances in Cryptology \u2013 Asiacrypt\u201999, Kwok-Yan Lam, Eiji Okamoto, and Chaoping Xing (Eds.)","author":"Abe M.","unstructured":"M. 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