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Simulation extractable SNARKs based on target linearly collision-resistant oracle

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Science china(Technological Sciences) 2024年第9期67卷 2853-2866页

作者： wang LiGuan LI Yuan ZHANG ShuangJun CAI DongLiang kan haibin shanghai Key Laboratory of Intelligent Information Processing School of Computer ScienceFudan UniversityShanghai 200433China shanghai Engineering Research Center of Blockchain Shanghai 200433China Yiwu Research Institute of fudan university Yiwu 322000China

The famous zero-knowledge succinct non-interactive arguments of knowledge(zk-SNARK) was proposed by Groth in ***, the construction is based on quadratic arithmetic programs which are highly efficient concerning the proof length and the verification complexity. Since then, there has been much progress in designing zk-SNARKs, achieving stronger security,and simulated extractability, which is analogous to non-malleability and has broad applications. In this study, following Groth's pairing-based zk-SNARK, a simulation extractability zk-SNARK under the random oracle model is constructed. Our construction relies on a newly proposed property named target linearly collision-resistant, which is satisfied by random oracles under discrete logarithm assumptions. Compared to the original Groth16 zk-SNARK, in our construction, both parties are allowed to use such a random oracle, aiming to get the same random number. The resulting proof consists of 3 group elements and only 1 pairing equation needs to be verified. Compared to other related works, our construction is shorter in proof length and simpler in verification while preserving simulation extractability. The results also extend to achieve subversion zero-knowledge SNARKs.

关键词： quadratic arithmetic program simulation extractability subversion zero-knowledge succinct non-interactive arguments of knowledge target linearly collision-resistant

mHealth中细粒度策略隐藏和可追踪去中心访问控制方案

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计算机研究与发展 2024年第6期61卷 1525-1535页

作者：王静怡阚海斌复旦大学计算机科学技术学院上海200433 上海市区块链工程技术研究中心上海200433 复旦大学义乌研究院浙江义乌322099

基于属性基加密的访问控制协议在个人健康档案共享中发挥着越来越重要的作用.但传统的基于密文策略属性基加密的访问控制方案存在着些许问题.首先,中心化的属性授权机构的抗风险能力低.其次,随密文发送未隐藏的访问策略可能会泄露患者... 详细信息

基于属性基加密的访问控制协议在个人健康档案共享中发挥着越来越重要的作用.但传统的基于密文策略属性基加密的访问控制方案存在着些许问题.首先,中心化的属性授权机构的抗风险能力低.其次,随密文发送未隐藏的访问策略可能会泄露患者的隐私.此外,传统方案难以追踪恶意泄露密钥的用户.为解决上述问题,提出一种适用于mHealth中细粒度策略隐藏和可追踪去中心访问控制方案.实现了去中心化的属性授权机构.属性由属性名称和属性值2部分构成,在加密阶段属性值隐藏在密文中,只对外公开通用的属性名称.当密钥遭到恶意泄露时,监管机构利用身份映射表可以追踪到恶意的用户.经过实验模拟和对比分析,所提方案在安全性方面和性能上适用于实际的mHealth环境.

关键词：属性基加密(ABE) 区块链访问控制策略隐藏可追踪性去中心化

THE GENERALIZED SMASH PRODUCT AND COPRODUCT

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Chinese Annals of mathematics,Series B 2000年第3期21卷 381-388页

作者： kan haibin(Department of Computer Science, fudan university, shanghai 200433, china.) E-mail: hbkan@*** Department of Computer Science Fudan University Shanghai 200433 China

The author discusses the braiding structures of the generalized smash product bialgebra and the cobraiding structures of the generalized smash coproduct bialgebra. It is pointed out that doublecrossed product determined by a cocycle is the generalized smash product and that doublecocrossed coproduct determined by a weak R-matrix is the generalized smash coproduct.

关键词： Generalized smash product Generalized coproduct Braiding structure Cobraiding structure

A characterization of solvability for a class of networks

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Science china(Information Sciences) 2012年第4期55卷 747-754页

作者： YUAN Chen & kan haibin shanghai Key Lab of Intelligent Information Processing,School of Computer Science,fudan university,shanghai 200433,china 1. shanghai Key Lab of Intelligent Information Processing School of Computer Science Fudan University Shanghai 200433 China

In this paper,we find that Property P can be generalized to characterize the solvability of a kind of networks with any number of sources,thus partially answering the open problem as to whether there are properties similar to Property P to characterize the solvability of some *** an application,for a given integer n,we construct such a solvable network that has no solvable solution if its alphabet size is less than n.

关键词： capacity coding capacity network coding solvability

The maximal rates and minimal decoding delay of more general complex orthogonal designs

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Science china(Information Sciences) 2010年第9期53卷 1826-1832页

作者： LI Yuan,kan haibin*,YUAN Chen & MA HuanFei The shanghai Key Lab of Intelligent Information Processing,School of Computer Science,fudan university,shanghai 200433,china 1. The shanghai Key Lab of Intelligent Information Processing School of Computer Science Fudan University Shanghai 200433 China

Space-time block codes based on complex orthogonal design have been widely investigated for their remarkable *** this paper,we propose a definition of more general complex orthogonal designs,which permits arbitrary complex factor with unit modulus in each *** prove that the maximal rate is still (m+1)/2m for n = 2m or 2m-1 antennas and minimal delay is also lower-bounded by(2m/(m-1)).Thus,allowing complex factor with unit modulus in each entry will not improve the main performance criterion of space-time block codes.

关键词： space-time block codes complex orthogonal design more general complex orthogonal design maximal rates minimal delays

A new scheme of digital communication using chaotic signals in MIMO channels

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Science china(Information Sciences) 2012年第10期55卷 2183-2193页

作者： MA HuanFei 1 & kan haibin 2 1 School of Mathematical Sciences,Soochow university,Suzhou 215006,china 2 School of Computer Science,fudan university,shanghai 200433,china 1. School of Mathematical Sciences Soochow University Suzhou 215006 China 2. School of Computer Science Fudan University Shanghai 200433 China

This paper proposes a new digital communication scheme,which uses chaotic signals based on the adaptive synchronization and parameter identification technique of chaotic systems reported *** to the multi signal character,this scheme combines the chaotic signal transmission with the MIMO channel technique in a wireless environment,which is different from the traditional chaotic communication *** a practical perspective,an outline of modulation,channel model,demodulation and non-coherent detection is ***,system performance is evaluated by simulations,and improvements on this scheme are also discussed.

关键词： chaotic modulation chaotic digital communication mapping parameters MIMO channel

Locally repairable codes from combinatorial designs

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Science china(Information Sciences) 2020年第2期63卷 174-188页

作者： Yu ZHANG haibin kan shanghai Key Laboratory of Intelligent Information Processing School of Computer ScienceFudan University fudan-Zhongan Joint Laboratory of Blockchain and Information Security Shanghai Engineering Research Center of Blockchain shanghai Institute for Advanced Communication and Data Science

Locally repairable codes（LRCs） were proposed to reduce the repair degree in distributed storage systems. In particular, LRCs with availability are highly desirable for distributed storage systems, since this kind of codes provide the mechanism of local repair for code symbols and parallel reading of hot *** this paper, we propose four types of（n, k, r, t）;LRCs from combinatorial designs. We introduce several constructions of LRCs with strict availability and some constructions of distance-optimal LRCs with information-symbol locality. Most of our constructions in this paper are over F;, i.e., they are suitable for implementation.

关键词： locally repairable codes erasure codes combinatorial designs distributed storage systems codes with availability

Construction of one special minimum storage regenerating code when α=2

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Science china(Information Sciences) 2015年第6期58卷 116-125页

作者： LIANG SongTao LIANG WenJuan kan haibin shanghai Key Laboratory of Intelligent Information Processing School of Computer ScienceFudan University College of Computer and Information Engineering Henan University

Regenerating codes is one class of erasure codes for distributed storage. A [n, k, d, α, β] regenerating code can recover the original message from any k out of n distributed storage nodes and repair any failed node from other arbitrary d nodes. α is the number of symbols stored in one node and β is the number of symbols downloaded by a newcomer node. Minimum storage regenerating(MSR) code is a regenerating code attaining the minimal storage requirement. In this paper, we address the design of a special MSR code where α = 2 and the first fragment of a node stores original symbol(we call it hybrid systematic MSR code or HS-MSR code). We point out that there exists no exact-repair construction when k 5. A simple exact linear construction is given when k = 2. Furthermore, by relaxing the condition of connecting any d nodes, we investigate the properties of quasi-cyclic regenerating code and propose a unified construction such that when k 3, repairing process can be achieved with less repair bandwidth by repair-by-transfer form.

关键词： array codes distributed storage network coding maximum-distance-separable(MDS) codes min-imum storage regenerating(MSR) codes

On the criteria for designing complex orthogonal space-time block codes

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Science china(Information Sciences) 2016年第8期59卷 153-163页

作者： haibin kan Xiaodong LIU Guangyue HAN School of Computer Science Fudan University shanghai Key Laboratory of Intelligent Information Processing Fudan University Department of mathematics University of Hong Kong

A complex orthogonal design(COD) used in space-time block codes is a kind of combinatorial design. It has been well studied because it has a fast maximum-likelihood decoding algorithm and achieves full diversity. When designing CODs, there are seven characteristics that should be considered, which include code rate, decoding delay, transceiver signal linearization, peak-to-average power ratio, etc. In this paper, we study the relationships among these design criteria. We prove that the maximum rate of generalized CODs(GCODs)that meet the last five criteria is 1/2. Moreover, we present a new method to construct GCODs based on *** this method on balanced complex orthogonal designs(BCODs), we obtain a novel class of GCODs that performs almost perfectly with respect to all the seven properties.

关键词： space-time block code complex orthogonal design decoding delay transceiver signal linearization peak-to-average power ratio(PAPR)