arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 2109.01727cs.CR
收藏

增加对抗性不确定性以扩展私有相似性测试

Increasing Adversarial Uncertainty to Scale Private Similarity Testing

Yiqing Hua, Armin Namavari, Kaishuo Cheng, Mor Naaman, Thomas Ristenpart

摘要:

社交媒体和其他平台依赖于对滥用内容的自动检测来帮助打击虚假信息、骚扰和滥用。一种常见的方法是根据有问题的项目的服务器端数据库检查用户内容的相似性。然而,这种方法从根本上危害了用户隐私。相反,我们的目标是客户端检测,只在发生此类匹配时通知用户,以警告他们不要使用滥用内容。我们的解决方案是基于隐私保护的相似性测试。现有的方法依赖于昂贵的加密协议,不能很好地扩展到大型数据库,并可能牺牲匹配的正确性。为了应对这一挑战,我们提出并形式化了基于相似性的桶化(SBB)的概念。使用SBB,客户端向数据库服务器显示少量信息,以便它可以生成潜在相似项的桶。桶足够小,以有效地应用隐私保护协议的相似性。为了分析所透露的信息的隐私风险,我们引入了一个框架,用于测量对手的信心,推断正确的客户端输入的谓词。我们开发了一个实用的SBB协议的图像内容,并评估其客户端的隐私保证与现实世界的社交媒体数据。然后,我们将SBB与各种相似性协议相结合,表明与SBB的组合在大规模数据库上提供了至少29倍的加速比,同时保留了超过95%的正确性。

英文摘要:

Social media and other platforms rely on automated detection of abusive content to help combat disinformation, harassment, and abuse. One common approach is to check user content for similarity against a server-side database of problematic items. However, this method fundamentally endangers user privacy. Instead, we target client-side detection, notifying only the users when such matches occur to warn them against abusive content. Our solution is based on privacy-preserving similarity testing. Existing approaches rely on expensive cryptographic protocols that do not scale well to large databases and may sacrifice the correctness of the matching. To contend with this challenge, we propose and formalize the concept of similarity-based bucketization~(SBB). With SBB, a client reveals a small amount of information to a database-holding server so that it can generate a bucket of potentially similar items. The bucket is small enough for efficient application of privacy-preserving protocols for similarity. To analyze the privacy risk of the revealed information, we introduce a framework for measuring an adversary's confidence in inferring a predicate about the client input correctly. We develop a practical SBB protocol for image content, and evaluate its client privacy guarantee with real-world social media data. We then combine SBB with various similarity protocols, showing that the combination with SBB provides a speedup of at least 29x on large-scale databases compared to that without, while retaining correctness of over 95%.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑