Location-based services have become prevalent and the risk of location privacy leakage increases. Most existing schemes use third-party-based or third-party-free system architectures; the former suffers from a single point of failure (SPOF) and the latter experiences a heavy load on user terminal equipment and higher communication costs. Ensuring location privacy while lowering system overhead becomes a challenge. Many existing schemes fail to leverage the responses from an LBS server; such responses can be cached to answer subsequent queries. As a result, providing users with a relatively comprehensive level of location privacy protection is troublesome. In this article, we propose a caching-based dual ${K}$ -anonymous (CDKA) location privacy-preserving scheme in edge computing environments. Our scheme employs an edge server to intercedes between a user and LBS the server. We reduce the load on the user device by applying multilevel caching and to protect location privacy through dual anonymity. To ensure the location privacy in our construction, we set mobile clients and edge servers as anonymous. We use caching to lower the communication overhead and enforce the location privacy. The security analysis of our scheme supports its robustness against the edge server and the LBS server privacy offenses. We rely on the computation time, the communication cost, and the cache hit ratio to evaluate our work against existing constructions. The results are twofold: our work possesses a better response rate down to 15–32.6 ms and exhibits lower communication cost requirements down to 6.2–38.9 kB compared to existing works. Our scheme witnesses a higher cache hit ratio of up to 13.6% and 39.1% compared to the literature.

中文翻译：

---

一种基于缓存的边缘计算双K-匿名位置隐私保护方案

基于位置的服务变得普遍，位置隐私泄露的风险增加。现有方案大多采用基于第三方或无第三方的系统架构；前者存在单点故障（SPOF），后者用户终端设备负载大，通信成本高。在降低系统开销的同时确保位置隐私成为一项挑战。许多现有方案无法利用 LBS 服务器的响应；可以缓存此类响应以回答后续查询。因此，为用户提供相对全面的位置隐私保护是一件很麻烦的事情。在本文中，我们提出了一种基于缓存的对偶 ${K}$ -边缘计算环境中的匿名（CDKA）位置隐私保护方案。我们的方案使用边缘服务器在用户和 LBS 服务器之间进行调解。我们通过应用多级缓存来减少用户设备上的负载，并通过双重匿名来保护位置隐私。为了确保我们建设中的位置隐私，我们将移动客户端和边缘服务器设置为匿名。我们使用缓存来降低通信开销并加强位置隐私。我们方案的安全性分析支持其对边缘服务器和 LBS 服务器隐私攻击的鲁棒性。我们依靠计算时间、通信成本和缓存命中率来评估我们针对现有结构的工作。结果是双重的：我们的工作具有更好的响应率，低至 15-32。6 毫秒，与现有作品相比，通信成本要求低至 6.2–38.9 kB。与文献相比，我们的方案见证了更高的缓存命中率，分别高达 13.6% 和 39.1%。