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Towards Efficient and Secure Access Control System for Mobile Cloud Computing

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China Communications 2015年第12期12卷 43-52页

作者： TU Shanshan huang yongfeng Department of Electronic Engineering Tsinghua University

This paper proposes a new access architecture onmobile cloud,which introduces a middle layer sitting between mobile devices and their cloud infrastructure.This middle layer is composed of cloudlets which are deployed by cloud services providers,such as wireless network access points(APs),to improve the performance of mobile cloud servicesand be different from traditional mobile operator mode.Then based on this new architecture.we improve our previous(Attribute-basedencryption) ABE access control scheme on cloud for mobile cloud,which is proposed to offload the main amount of computations to the cloudlet as the function of cloud.Simulationresults demonstratethe new access control scheme takes into consideration response time constraints and network statusof access task execution,while satisfying certain network security for mobile cloud.

关键词：移动设备网络安全访问控制系统计算服务提供商网络接入点控制方案基础设施

Enabling Efficient Batch Updating Verification for Multi-versioned Data in Cloud Storage

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Chinese Journal of Electronics 2019年第2期28卷 377-385页

作者： QI Yining TANG Xin huang yongfeng Department of Electronic Engineering Tsinghua University Tsinghua National Laboratory for Information Science and Technology

Existing dynamic data possession verification schemes not only suffer from low efficiency of rebalancing its Merkle Hash tree(MHT) when executing data updating, but also lack effective mechanism to verify multi-version files. Aiming at these problems, this paper propose a new data structure called Rank-based multi-version Merkle AVL tree(RBMV-MAT) to achieve efficient batch updating verification for multi-version data.RBMV-MAT uses a special lock and relaxed balance to decrease the frequency of rebalacing operations. The experimental results show that our efficient scheme has better efficiency than those of existing methods.

关键词： Cloud storage Data integrity Provable data possession(PDP) Data dynamics Cloud computing

DIRA: Enabling decentralized data integrity and reputation audit via blockchain

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Science China(Technological Sciences) 2019年第4期62卷 698-701页

作者： QI YiNing huang yongfeng Department of Electronic Engineering Tsinghua University Tsinghua National Laboratory for Information Science and Technology

Nowadays more data are being generated than ever before and cloud computing has undoubtedly become one of the most important platforms for dealing with their huge demand.However,there are still a series of concerns th... 详细信息

关键词： data computing concerns

An Effective and Secure Access Control System Scheme in the Cloud

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Chinese Journal of Electronics 2015年第3期24卷 524-528页

作者： NIU Shaozhang TU Shanshan huang yongfeng Beijing Key Lab of Intelligent Telecommunication Software and Multimedia Beijing University of Posts and Telecommunications Department of Electronic Engineering Tsinghua University

Cloud computing services have got rapid development in the field of the lightweight terminal, especially wireless communications. The comprehensive access control system framework is proposed for the cloud. A kind of access control scheme based on attribute encryption is designed, in which lightweight devices can safely use cloud computing resources to outsource encrypt/decrypt operations, and not worry for exposing terminal sensitive data.The scheme is verified by performance evaluation about the security, computing, storage, to ensure the legitimate interests of users in the cloud.

关键词： Cloud computing Access control Attribute encryption Security and efficiency

Privacy-Preserving Public Auditing Scheme for Data Confidentiality and Accountability in Cloud Storage

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Chinese Journal of Electronics 2019年第1期28卷 179-187页

作者： YANG Zhen WANG Wenyu huang yongfeng LI Xing Department of Electronic Engineering Tsinghua University Tsinghua National Laboratory for Information Science and Technology Information Networking Institute Carnegie Mellon University

Cloud data confidentiality need to be audited for the data owner’s concern. Confidentiality auditing is usually based on logging schemes, whereas cloud data dynamics and sharing group dynamics result in massive logs, which makes confidentiality auditing a formidable task for user with limited resources. So we propose a public auditing scheme for data confidentiality,in which user resorts to a Third-party auditor(TPA)for auditing. Our scheme design a special log called attestation in which hash user pseudonym is used to preserve user privacy. Attestation-based data access identifying is presented in our scheme which brings no new vulnerabilities toward data confidentiality and no extra online burden for user. We further support accountability of responsible user for data leakage based on user pseudonym. Extensive security and performance analysis compare our scheme with existing auditing schemes.Results indicate that the proposed scheme is provably secure and highly efficient.

关键词： Data confidentiality Public auditability Privacy preserving Cloud storage User accountability

Steganography in low bit-rate speech streams based on quantization index modulation controlled by keys

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Science China(Technological Sciences) 2017年第10期60卷 1585-1596页

作者： huang yongfeng TAO HuaiZhou XIAO Bo CHANG ChinChen Department of Electronic Engineering Tsinghua University Department of Information Engineering and Computer Science Feng Chia University

Since low bit-rate speech codecs used for voice over internet protocol(VoIP), such as iLBC(internet low bit-rate codec), G.723.1and G.729 A, have less redundancy due to high compression, it is more challenging to embed information in low bit-rate speech streams of VoIP. In this study, a new method is proposed for steganography in low bit-rate speech streams of VoIP. The core idea of this method is setting up a graph model for the codebook space of the quantizer. Based on the graph model, the method realises a quantization index modulation(QIM)-controlled algorithm for partitioning the codebook space. It can be proved that this method can minimize signal distortion while steganography taking place. Taking into account codeword partition balance and partition diversity, the proposed steganographic algorithm was based on QIM controlled by secret keys, i.e., mapping the ways of codebook division into secret keys, thereby significantly improving the undetectability and robustness of VoIP steganography. Performance measurements and steganalysis experiments showed that the proposed QIM-controlled steganographic algorithm was more secure and robust than the QIM algorithm, the conventional RANDOM algorithm and the original codebook algorithm.

关键词：语音编解码器低比特率量化器调制索引 G.723.1 控制算法 VoIP

不同中草药植物提取物对香蕉枯萎病菌抑菌活性评价

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广东农业科学 2024年第3期51卷 48-55页

作者：黄永丰项丹丹江振兴李春雨胡位荣广州大学生命科学学院广东广州510006 广东省农业科学院果树研究所/农业农村部南亚热带果树生物学与遗传资源利用重点实验室/广东省热带亚热带果树研究重点实验室广东广州510640 仲恺农业工程学院园艺园林学院广东广州510225

【目的】探究不同中草药提取物对香蕉枯萎病菌的抑菌效果,筛选防治香蕉枯萎病的有效植物资源。【方法】选取大黄、穿心莲等29种中草药,采用乙醇浸提法提取中草药植物中的有效活性成分,应用生长速率法检测各提取物对香蕉枯萎病菌4号生理... 详细信息

【目的】探究不同中草药提取物对香蕉枯萎病菌的抑菌效果,筛选防治香蕉枯萎病的有效植物资源。【方法】选取大黄、穿心莲等29种中草药,采用乙醇浸提法提取中草药植物中的有效活性成分,应用生长速率法检测各提取物对香蕉枯萎病菌4号生理小种(Foc TR4)的抑制作用,使用石油醚、氯仿、乙酸乙酯、正丁醇4种不同极性溶剂对大黄的乙醇粗提物进行分级萃取,利用悬滴法测定提取物对香蕉枯萎病菌孢子萌发的抑制作用,并观察提取物对香蕉枯萎病菌菌丝形态的影响。【结果】29种中草药提取物对Foc TR4的抑菌效果表现出较大差异,大黄、穿心莲、苦参、野菊花4种提取物对Foc TR4的抑菌效果较好,其中大黄提取物的抑制作用最佳,6 mg/mL大黄提取物的抑菌率为48.57%,对菌丝生长的EC_(50)值为6.68 mg/mL,抑制孢子萌发的EC_(50)值为4.60 mg/mL;通过光学显微镜观察,大黄提取物对Foc TR4菌丝具有一定破坏作用,使菌丝产生大量分枝和黏连并造成菌丝生长不均匀等现象;大黄乙醇粗提物的石油醚、氯仿、乙酸乙酯、正丁醇4个萃取组分中,乙酸乙酯萃取组分对Foc TR4菌丝生长和孢子萌发抑制效果最佳,其浓度为10 mg/mL时,对菌丝生长的抑制率可达85.68%;大黄提取物乙酸乙酯萃取组分对Foc TR4菌丝生长的EC_(50)值为0.16 mg/mL。【结论】从29种中草药提取物中筛选出了抑菌效果较好的大黄提取物,并进一步明确其对香蕉枯萎病菌Foc TR4的主要有效抑菌成分在乙酸乙酯萃取组分中,可为研发防治香蕉枯萎病的植物源新农药提供参考。

关键词：中草药植物提取物分离组分香蕉枯萎病抑菌活性

Blockchain-based Privacy-Preserving Group Data Auditing with Secure User Revocation

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Computer Systems Science & Engineering 2023年第4期45卷 183-199页

作者： Yining Qi Yubo Luo yongfeng huang Xing Li Tsinghua University Beijing100084China Beijing National Research Center for Information Science and Technology Beijing100084China University of North Carolina at Chapel Hill North Carolina27599USA

Progress in cloud computing makes group data sharing in outsourced storage a reality.People join in group and share data with each other,making team work more convenient.This new application scenario also faces data security threats,even more complex.When a user quit its group,remaining data block signatures must be re-signed to ensure security.Some researchers noticed this problem and proposed a few works to relieve computing overhead on user side.However,considering the privacy and security need of group auditing,there still lacks a comprehensive solution to implement secure group user revocation,supporting identity privacy preserving and collusion attack resistance.Aiming at this target,we construct a concrete scheme based on ring signature and smart contracts.We introduce linkable ring signature to build a kind of novel meta data for integrity proof enabling anonymous verification.And the new meta data supports secure revocation.Meanwhile,smart contracts are using for resisting possible collusion attack and malicious re-signing computation.Under the combined effectiveness of both signature method and blockchain smart contracts,our proposal supports reliable user revocation and signature re-signing,without revealing any user identity in the whole process.Security and performance analysis compared with previous works prove that the proposed scheme is feasible and efficient.

关键词： Provable data possession data integrity blockchain ring signature

Blockchain-Based Privacy-Preserving Public Auditing for Group Shared Data

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Intelligent Automation & Soft Computing 2023年第3期35卷 2603-2618页

Cloud storage has been widely used to team work or cooperation devel-opment.Data owners set up groups,generating and uploading their data to cloud storage,while other users in the groups download and make use of it,which is called group data sharing.As all kinds of cloud service,data group sharing also suffers from hardware/software failures and human errors.Provable Data Posses-sion(PDP)schemes are proposed to check the integrity of data stored in cloud without downloading.However,there are still some unmet needs lying in auditing group shared data.Researchers propose four issues necessary for a secure group shared data auditing:public veriﬁcation,identity privacy,collusion attack resis-tance and traceability.However,none of the published work has succeeded in achieving all of these properties so far.In this paper,we propose a novel block-chain-based ring signature PDP scheme for group shared data,with an instance deployed on a cloud server.We design a linkable ring signature method called Linkable Homomorphic Authenticable Ring Signature(LHARS)to implement public anonymous auditing for group data.We also build smart contracts to resist collusion attack in group auditing.The security analysis and performance evalua-tion prove that our scheme is both secure and efﬁcient.

关键词： Provable data possession data integrity blockchain ring signature