Confused Modulo Projection based Somewhat Homomorphic Encryption -- Cryptosystem, Library and Applications on Secure Smart Cities
Beijing Electronic Science and Technology Institute（北京电子科技学院）；State Key Laboratory of Cryptology（密码学国家重点实验室）；Beijing University of Posts and Telecommunications（北京邮电大学）；Minzu University of China（中央民族大学）；NIT Patna（印度国家理工学院巴特那分校）；Kyushu Institute of Technology（九州工业大学）
Xin Jin, Hongyu Zhang, Xiaodong Li, Haoyang Yu, Beisheng Liu, Shujiang Xie, Amit Kumar Singh, Yujie Li
备注：
IEEE Internet of Things Journal (IOTJ), Published Online: 7 August 2020
With the development of cloud computing, the storage and processing of massive visual media data has gradually transferred to the cloud server. For example, if the intelligent video monitoring system cannot process a large amount of data locally, the data will be uploaded to the cloud. Therefore, how to process data in the cloud without exposing the original data has become an important research topic. We propose a single-server version of somewhat homomorphic encryption cryptosystem based on confused modulo projection theorem named CMP-SWHE, which allows the server to complete blind data processing without \emph{seeing} the effective information of user data. On the client side, the original data is encrypted by amplification, randomization, and setting confusing redundancy. Operating on the encrypted data on the server side is equivalent to operating on the original data. As an extension, we designed and implemented a blind computing scheme of accelerated version based on batch processing technology to improve efficiency. To make this algorithm easy to use, we also designed and implemented an efficient general blind computing library based on CMP-SWHE. We have applied this library to foreground extraction, optical flow tracking and object detection with satisfactory results, which are helpful for building smart cities. We also discuss how to extend the algorithm to deep learning applications. Compared with other homomorphic encryption cryptosystems and libraries, the results show that our method has obvious advantages in computing efficiency. Although our algorithm has some tiny errors ($10^{-6}$) when the data is too large, it is very efficient and practical, especially suitable for blind image and video processing.
We propose a new homomorphic public-key cryptosystem over arbitrary nonidentity finite group based on the difficulty of the membership problem for groups of integer matrices. Besides, a homomorphic cryptosystem is designed for the first time over finite commutative rings.
In this paper homomorphic cryptosystems are designed for the first time over any finite group. Applying Barrington's construction we produce for any boolean circuit of the logarithmic depth its encrypted simulation of a polynomial size over an appropriate finitely generated group.
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The University of Tokyo（东京大学）；Michigan State University（密歇根州立大学）；Carnegie Mellon University（卡内基梅隆大学）
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CERN（欧洲核子研究组织）；Universidad Carlos III de Madrid（马德里卡洛斯三世大学）
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Hong Kong University of Science and Technology（香港科技大学）；Clustar（星辰天合）；Peng Cheng Lab（鹏城实验室）
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ComputeFHE: A Privacy-Preserving General-Purpose Computation Library
Department of Computer Engineering, Çankaya University, Ankara, Turkey（计算机工程系，恰纳卡大学，安卡拉，土耳其）；Computer Programming Program, Çankaya University, Ankara, Turkey（计算机编程项目，恰纳卡大学，安卡拉，土耳其）
