{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,16]],"date-time":"2026-10-16T06:40:55Z","timestamp":1792132855379,"version":"4.4.0"},"reference-count":34,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2023,1,19]],"date-time":"2023-01-19T00:00:00Z","timestamp":1674086400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Natural Science Foundation of Hebei Province, China","award":["F2019201427"],"award-info":[{"award-number":["F2019201427"]}]},{"name":"Natural Science Foundation of Hebei Province, China","award":["2017A20004"],"award-info":[{"award-number":["2017A20004"]}]},{"name":"Natural Science Foundation of Hebei Province, China","award":["HB19TQ001"],"award-info":[{"award-number":["HB19TQ001"]}]},{"name":"Fund for Integration of Cloud Computing and Big Data, Innovation of Science and Education of China","award":["F2019201427"],"award-info":[{"award-number":["F2019201427"]}]},{"name":"Fund for Integration of Cloud Computing and Big Data, Innovation of Science and Education of China","award":["2017A20004"],"award-info":[{"award-number":["2017A20004"]}]},{"name":"Fund for Integration of Cloud Computing and Big Data, Innovation of Science and Education of China","award":["HB19TQ001"],"award-info":[{"award-number":["HB19TQ001"]}]},{"name":"Social Science Foundation of Hebei Province, China","award":["F2019201427"],"award-info":[{"award-number":["F2019201427"]}]},{"name":"Social Science Foundation of Hebei Province, China","award":["2017A20004"],"award-info":[{"award-number":["2017A20004"]}]},{"name":"Social Science Foundation of Hebei Province, China","award":["HB19TQ001"],"award-info":[{"award-number":["HB19TQ001"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Entropy"],"abstract":"<jats:p>Users who initiate continuous location queries are prone to trajectory information leakage, and the obtained query information is not effectively utilized. To address these problems, we propose a continuous location query protection scheme based on caching and an adaptive variable-order Markov model. When a user initiates a query request, we first query the cache information to obtain the required data. When the local cache cannot satisfy the user\u2019s demand, we use a variable-order Markov model to predict the user\u2019s future query location and generate a k-anonymous set based on the predicted location and cache contribution. We perturb the location set using differential privacy, then send the perturbed location set to the location service provider to obtain the service. We cache the query results returned by the service provider to the local device and update the local cache results according to time. By comparing the experiment with other schemes, the proposed scheme in this paper reduces the number of interactions with location providers, improves the local cache hit rate, and effectively ensures the security of the users\u2019 location privacy.<\/jats:p>","DOI":"10.3390\/e25020201","type":"journal-article","created":{"date-parts":[[2023,1,19]],"date-time":"2023-01-19T08:22:36Z","timestamp":1674116556000},"page":"201","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":9,"title":["Cache-Based Privacy Protection Scheme for Continuous Location Query"],"prefix":"10.3390","volume":"25","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7466-4622","authenticated-orcid":false,"given":"Zhenpeng","family":"Liu","sequence":"first","affiliation":[{"name":"Information Technology Center, Hebei University, Baoding 071002, China"},{"name":"School of Cyber Security and Computer, Hebei University, Baoding 071002, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dewei","family":"Miao","sequence":"additional","affiliation":[{"name":"School of Cyber Security and Computer, Hebei University, Baoding 071002, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ruilin","family":"Li","sequence":"additional","affiliation":[{"name":"School of Cyber Security and Computer, Hebei University, Baoding 071002, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yi","family":"Liu","sequence":"additional","affiliation":[{"name":"Information Technology Center, Hebei University, Baoding 071002, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xiaofei","family":"Li","sequence":"additional","affiliation":[{"name":"Information Technology Center, Hebei University, Baoding 071002, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,1,19]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1323","DOI":"10.1016\/j.procs.2020.04.141","article-title":"Towards Privacy-Preserving Dummy Generation in Location-Based Services","volume":"171","author":"Dilay","year":"2020","journal-title":"Procedia Comput. 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