Collaborative Research: SaTC: CORE: Small: Expanding the Realm of Oblivious Transfer: New Tools for Cryptography

如今，大量的个人信息被许多实体收集用于提供各种服务。由于所收集数据的敏感性，开发能够在大数据上进行隐私保护计算的技术和工具的需求比以往任何时候都更加必要。该项目旨在增强不经意传输（OT）的功能，安全性和效率，这是密码学中的一个基本原语，其更广泛的目标是在理论和实践中提高密码系统的效率和可用性，特别是在大数据时代。该项目的创新之处在于开发在隐私保护协议的设计中发挥不可或缺的作用的工具。这样的协议具有社会效益，可以在保持数据隐私的同时对敏感数据进行计算。该项目的影响包括为许多重要的现实世界应用实现更有效的协议，并加深我们对与OT相关的密码学许多领域的有效构造和基本限制的理解，例如安全多方计算，零知识证明，高级加密类型等。研究人员将他们的研究成果整合到本科和研究生课程的课程中，并致力于指导和建议各级学生，从本科到博士，特别是那些来自计算领域代表性不足的群体的学生。首先，研究人员设计了具有高级功能和增强安全性的OT的有效结构，这些结构可以在加密系统中更好地利用。这些OT概念提供了在各种环境中降低通信和计算成本的功能，使其成为大数据应用中不可或缺的工具。其次，该项目调查了一个与OT有密切联系的特定MPC问题。特别是利用先进的OT工具，研究者们提高了私有集交集（PSI）协议的效率，丰富了PSI协议的功能，使PSI协议在实际中得到了广泛的应用。最后，该项目确定并正式确定可能存在的障碍，反对上述目标;这是通过证明为上述目标的假设复杂性或建设效率的下限来实现的。该奖项反映了NSF的法定使命，并已被认为是值得通过使用基金会的智力价值和更广泛的影响审查标准进行评估的支持。

Nowadays, vast amounts of individual information are collected by numerous entities for providing a variety of services. Due to the sensitive nature of the collected data, the need for developing techniques and tools that enable privacy-preserving computation on big data is more necessary than ever. This project aims to enhance the functionality, security, and efficiency of oblivious transfer (OT), a fundamental primitive in cryptography, with a broader goal of improving the efficiency and usability of cryptographic systems in both theory and practice, especially in the era of big data. The project's novelties are developing tools that play an integral role in the design of privacy-preserving protocols. Such protocols have societal benefits, enabling computation on sensitive data while keeping the data private. The project's impacts include achieving more efficient protocols for many important real-world applications and deepening our understanding of efficient constructions and fundamental limits in many areas in cryptography that are related to OT, such as secure multi-party computation, zero-knowledge proofs, advanced types of encryption and more. The investigators integrate their research results into curricula for both undergraduate and graduate level courses and are committed to mentoring and advising students at all levels, from undergraduate to PhD, especially those from under-represented groups in computing.The project focuses on three main thrusts to expand the realm of oblivious transfer. First, the investigators design efficient constructions of OT with advanced functionality and strengthened security, which can be better leveraged in cryptographic systems. These OT notions provide features for reducing communication and computation costs in various settings, making them indispensable tools in big-data applications. Second, the project investigates a specific MPC problem that has close connections to OT. In particular, using advanced OT tools, the investigators improve the efficiency and enrich the functionality of private set intersection (PSI) protocols, which have wide applications in practice. Finally, the project identifies and formalizes barriers that may exist against the above goals; this is carried out by proving lower bounds on the assumption complexity or efficiency of constructions for the above goals.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.