As vehicular equipment is becoming more and more intelligent, the vehicular information service, as the main means of capturing information, has been far from able to meet the needs of occupants [1, 2]. Cloud computing, with its powerful computing and storage capabilities, convenient network access, energy saving and excellent scalability, reliability, availability, and other advantages, can be an effective solution to the limitations of existing automotive information services. Connected vehicular cloud computing, which combines cloud computing and VANETs, has the characteristics of both a cloud platform and a mobile ad hoc network, including autonomy and no fixed structure, good scalability, and so on. However, during the information retrieval, high-density node distribution and high-speed mobile nodes may directly affect the information transmission capacity of a VANET by information tampering, transmission delay, and other issues. In this article, we propose a ciphertext-based search system that exploits RSUs as super peers for connected vehicular cloud computing. The proposed system supports ciphertext retrieval for related documents. In the proposed system, all the computations and retrieval operations are handled by super stationary peers, while documents are stored in the cloud to achieve high efficiency and security of the index structure. We can also reduce the impact of vehicle dynamics on the information retrieval process in this way. In our system, the indexing efficiency is also improved by utilizing a hybrid indexing structure in which binary trees are nested in a B+ tree. Through security analysis and performance evaluation, we demonstrate that our proposal can achieve acceptable security and efficiency.

中文翻译：

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互联车辆云计算中安全高效的隐私保护密文检索


随着车载设备越来越智能化，车载信息服务作为获取信息的主要手段，已经远远不能满足驾乘人员的需求[1, 2]。云计算以其强大的计算和存储能力、便捷的网络接入、节能以及优异的可扩展性、可靠性、可用性等优势，可以有效解决现有汽车信息服务的局限性。车联网云计算将云计算与VANET相结合，兼具云平台和移动自组织网络的特点，包括自主性、无固定结构、良好的可扩展性等。然而，在信息检索过程中，高密度的节点分布和高速移动的节点可能会因信息篡改、传输延迟等问题直接影响VANET的信息传输能力。在本文中，我们提出了一种基于密文的搜索系统，该系统利用 RSU 作为互联车辆云计算的超级对等点。所提出的系统支持相关文档的密文检索。在所提出的系统中，所有计算和检索操作均由超级固定节点处理，而文档存储在云端，以实现索引结构的高效性和安全性。我们还可以通过这种方式减少车辆动力学对信息检索过程的影响。在我们的系统中，通过利用二叉树嵌套在B+树中的混合索引结构，索引效率也得到了提高。通过安全分析和性能评估，我们证明我们的建议可以达到可接受的安全性和效率。