Graph encryption schemes play a crucial role in facilitating secure queries on encrypted graphs hosted on untrusted servers. With applications spanning navigation systems, network topology, and social networks, the need to safeguard sensitive data becomes paramount. Existing graph encryption methods, however, exhibit vulnerabilities by inadvertently revealing aspects of the graph structure and query patterns, posing threats to security and privacy. In response, we propose a novel graph encryption scheme designed to mitigate access pattern and query pattern leakage through the integration of oblivious RAM and trusted execution environment techniques, exemplified by a Trusted Execution Environment (TEE). Our solution establishes two key security objectives: (1) ensuring that adversaries, when presented with an encrypted graph, remain oblivious to any information regarding the underlying graph, and (2) achieving query indistinguishability by concealing access patterns. Additionally, we conducted experimentation to evaluate the efficiency of the proposed schemes when dealing with real-world location navigation services.

翻译：图加密方案在促进对不可信服务器上加密图的安全查询方面发挥着关键作用。随着导航系统、网络拓扑和社交网络等应用领域的扩展，保护敏感数据的需求变得至关重要。然而，现有的图加密方法因无意中泄露图结构和查询模式的某些方面而存在漏洞，对安全性和隐私构成威胁。为此，我们提出了一种新颖的图加密方案，旨在通过集成不经意随机存取存储器和可信执行环境技术（以可信执行环境为例）来缓解访问模式和查询模式的泄露。我们的方案确立了两个关键安全目标：(1) 确保攻击者在面对加密图时，对底层图的任何信息均无从知晓；(2) 通过隐藏访问模式实现查询不可区分性。此外，我们通过实验评估了所提方案在处理现实世界位置导航服务时的效率。