报告题目：Towards Practical Threshold Homomorphic Encryption for Large-Scale Applications
报告人：常益嘉博士（香港科技大学）
报告时间：2025年10月13日（周一）下午2:30—4:30
报告地点：犀浦校区 X9428
邀请人：朱金宝 特聘副研究员
报告内容：Threshold homomorphic encryption (ThHE) is a special encryption scheme with extensive applications in secure multi-party computation (MPC). Despite advancements in ThHE over the past three decades, existing ThHE schemes still suffer from either inefficient decryption characterized by a high complexity with respect to the number of parties, or extra restrictions that limit their flexible utility in practice. Although ThHE has many advantages over other cryptographic tools, this efficiency-utility dilemma may hinder its widespread use, especially for large-scale applications with numerous parties. This talk will presents some advances in resolving this dilemma for two types of ThHE that are demonstrated to be very useful for MPC. The related works will make ThHE more practical and more attractive for large-scale applications, while also provides new cryptographic primitives that can be of independent interests.
报告人简介：Yijia Chang received his Ph.D. degree from Hong Kong University of Science and Technology (Guangzhou campus) in 2025. Before that, he received Bachelor degree from Xidian University in 2018 and Master degree from ShanghaiTech University in 2022. His research interests are making cryptographic primitives more practical and AI security more formal, with a focus on homomorphic encryption and AI model ownership verification. His work is published in top-tier conferences such as IACR Crypto and USENIX Security.