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基于贡献值和难度值的高可靠性区块链共识机制 CQVIP CSCD
期刊论文 | 2021 , 44 (1) , 162-176 | 计算机学报
摘要&关键词 引用

摘要 :

基于贡献值证明(PoC)的区块链共识机制是面向知识产权保护与交易应用场景提出的一种区块链共识机制,通过计算节点用户的贡献值,由贡献值最大的节点获得新区块的记账权.然而,由于PoC会造成记账节点具有很强的确定性,一旦该节点未能正常完成记账出块,网络中其它节点将始终保持在挂起等待状态,系统将陷于停滞状态,无法继续运行.为了使PoC区块链共识机制能够适用于公有链应用场景,本文提出基于贡献值和难度值(PoC+PoW)的区块链共识机制,使选择新区块记账权的节点具备一定的不确定性,能够有效解决PoC共识机制中存在的系统运行挂起缺陷.在PoC+PoW共识机制中,节点在工作量证明(PoW)竞争中所对应数学难题的难度值根据节点的贡献值(PoC)进行动态确定,是一种对单纯基于PoC共识机制的灾备方案,以确保系统运行的可靠性.本文提出的PoC+PoW方案根据节点的贡献值排名为节点分配相应的PoW难度值,节点再通过PoW共识机制竞争记账权.引入PoW后的共识机制最大程度地尊重PoC贡献值排名,使节点的记账出块率与其贡献值成高度正比,在系统运行层面则保证记账出块率达到或无限趋近100%,有效解决PoC带来的系统运行挂起问题.本文从节点贡献值排名、相邻贡献值节点间值差以及分组方式三个角度设计PoW难度值分配算法,并通过实验验证难度值分配算法的合理性和有效性.同时,通过实验与传统PoC共识机制在记账出块时延方面进行对比分析,进一步验证了PoC+PoW方案的优越性和可行性.

关键词 :

工作量证明 工作量证明 区块链 区块链 贡献值 贡献值 共识机制 共识机制 难度值 难度值 贡献值证明 贡献值证明

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GB/T 7714 何泾沙 , 张琨 , 薛瑞昕 et al. 基于贡献值和难度值的高可靠性区块链共识机制 [J]. | 计算机学报 , 2021 , 44 (1) : 162-176 .
MLA 何泾沙 et al. "基于贡献值和难度值的高可靠性区块链共识机制" . | 计算机学报 44 . 1 (2021) : 162-176 .
APA 何泾沙 , 张琨 , 薛瑞昕 , 朱娜斐 , 贺鹏 , 宋洪宇 et al. 基于贡献值和难度值的高可靠性区块链共识机制 . | 计算机学报 , 2021 , 44 (1) , 162-176 .
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一种基于本体推理的隐私信息访问控制方法及系统 incoPat
专利 | 2021-01-15 | CN202110056973.7
摘要&关键词 引用

摘要 :

本发明提供一种基于本体推理的隐私信息访问控制方法及系统,涉及隐私保护领域,访问者发出访问请求,包括访问者账号和需访问信息;从资源服务器获取需访问信息中隐私主体的所有隐私信息点;根据隐私主体预设的隐私需求,包括阈值,获取各隐私信息点的隐私泄露值;根据各隐私信息点的隐私泄露值计算隐私主体泄露值;判断隐私主体泄露值是否大于阈值,若大于阈值,则拒绝访问者的访问;若小于或等于阈值,则根据访问者账号获取访问者的历史访问信息,结合历史访问信息和需访问信息计算新的隐私主体泄露值,若新的隐私主体泄露值大于阈值,则拒绝访问;若新的隐私主体泄露值小于等于阈值,则允许访问。本发明实现更加细粒度的个性化的访问控制。

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GB/T 7714 何泾沙 , 靳姝婷 , 朱娜斐 et al. 一种基于本体推理的隐私信息访问控制方法及系统 : CN202110056973.7[P]. | 2021-01-15 .
MLA 何泾沙 et al. "一种基于本体推理的隐私信息访问控制方法及系统" : CN202110056973.7. | 2021-01-15 .
APA 何泾沙 , 靳姝婷 , 朱娜斐 , 潘世佳 , 陈宝存 . 一种基于本体推理的隐私信息访问控制方法及系统 : CN202110056973.7. | 2021-01-15 .
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基于本体推理的隐私保护访问控制机制研究 CSCD
期刊论文 | 2021 , 21 (08) , 52-61 | 信息网络安全
摘要&关键词 引用

摘要 :

通过访问控制的方法保护用户隐私被研究者们采纳,访问控制通过验证访问者的身份的合法性来限制非法用户对数据的访问,从而有效避免隐私泄露。但目前该方法存在不考虑用户隐私信息、访问控制粒度较粗等问题,不能满足所有隐私主体的需求,也不能最大限度地保护用户的隐私信息。文章提出一种基于本体推理的隐私信息保护访问控制机制,该机制能够从所有隐私主体的隐私信息角度出发,用本体推理的方法从访问控制粒度方面进行信息优化,从隐私主体的角度考虑更多隐私主体的隐私需求。实验结果表明文章提出的访问控制机制能够更好地保护用户隐私。

关键词 :

本体推理 本体推理 隐私保护 隐私保护 语义分析 语义分析 访问控制 访问控制

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GB/T 7714 靳姝婷 , 何泾沙 , 朱娜斐 et al. 基于本体推理的隐私保护访问控制机制研究 [J]. | 信息网络安全 , 2021 , 21 (08) : 52-61 .
MLA 靳姝婷 et al. "基于本体推理的隐私保护访问控制机制研究" . | 信息网络安全 21 . 08 (2021) : 52-61 .
APA 靳姝婷 , 何泾沙 , 朱娜斐 , 潘世佳 . 基于本体推理的隐私保护访问控制机制研究 . | 信息网络安全 , 2021 , 21 (08) , 52-61 .
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Detection and Prevention of Jellyfish Attacks Using kNN Algorithm and Trusted Routing Scheme in MANET EI
期刊论文 | 2021 , 23 (1) , 77-87 | International Journal of Network Security
摘要&关键词 引用

摘要 :

Mobile ad hoc networks (MANETs) are surrounded by various vulnerabilities and attacks due to open medium, dynamic topology, limited energy, and absence of central control. In MANET, each attack has different behavior and aftermaths. DoS attack is one of the serious attacks in MANET, which disturbs the normal routing process. Jellyfish (JF) attack is a type of DoS attack in MANET, whose dynamic behavior makes it quite difficult to detect such attacks. In this paper, we propose a technique to detect the jellyfish attack in MANET. The proposed technique combines the authentication and trustworthiness of nodes and the kNN algorithm for the identification of jellyfish attacks in which each and every node calculates the primary and secondary trust values to detect the attacking node by the recommendation of neighboring nodes and trust metrics. The kNN algorithm separates the jellyfish nodes from other legitimate nodes based on the differences in their behavior. The proposed technique would then pick reliable nodes by the hierarchical trust assessment property of nodes to perform packet routing. The experiment shows that the proposed technique could decrease delay and increase the throughput of the network by avoiding jellyfish nodes. © 2021

关键词 :

Learning algorithms Learning algorithms Routing algorithms Routing algorithms Denial-of-service attack Denial-of-service attack Mobile security Mobile security Nearest neighbor search Nearest neighbor search Mobile ad hoc networks Mobile ad hoc networks

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GB/T 7714 Zardari, Zulfiqar Ali , He, Jingsha , Pathan, Muhammad Salman et al. Detection and Prevention of Jellyfish Attacks Using kNN Algorithm and Trusted Routing Scheme in MANET [J]. | International Journal of Network Security , 2021 , 23 (1) : 77-87 .
MLA Zardari, Zulfiqar Ali et al. "Detection and Prevention of Jellyfish Attacks Using kNN Algorithm and Trusted Routing Scheme in MANET" . | International Journal of Network Security 23 . 1 (2021) : 77-87 .
APA Zardari, Zulfiqar Ali , He, Jingsha , Pathan, Muhammad Salman , Qureshi, Sirajuddin , Hussain, Muhammad Iftikhar , Razaque, Fahad et al. Detection and Prevention of Jellyfish Attacks Using kNN Algorithm and Trusted Routing Scheme in MANET . | International Journal of Network Security , 2021 , 23 (1) , 77-87 .
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区块链数字货币交易的识别方法、装置、电子设备及存储介质 incoPat
专利 | 2021-01-21 | CN202110083604.7
摘要&关键词 引用

摘要 :

本发明公开了一种区块链数字货币的识别方法、装置、电子设备及存储介质,属于数字货币技术领域,包括获取数字货币的交易数据,并对交易数据按照交易地址进行聚类,绘制数字货币交易图,按照社群划分成多个社区;采用复杂网络分析方法计算每个社区的网络分析图指标;获取已知数字货币的交易图结构,并计算出已知数字货币的交易图结构的网络分析图指标;将所有的社区和已知数字货币的交易图结构合并组成数据集;对数据集进行识别,识别出数据集中的交易图结构。本发明可以识别数字货币的交易图结构和交易模式。

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GB/T 7714 朱娜斐 , 薛瑞昕 , 何泾沙 et al. 区块链数字货币交易的识别方法、装置、电子设备及存储介质 : CN202110083604.7[P]. | 2021-01-21 .
MLA 朱娜斐 et al. "区块链数字货币交易的识别方法、装置、电子设备及存储介质" : CN202110083604.7. | 2021-01-21 .
APA 朱娜斐 , 薛瑞昕 , 何泾沙 , 何琳 , 王雅静 , 宋洪宇 et al. 区块链数字货币交易的识别方法、装置、电子设备及存储介质 : CN202110083604.7. | 2021-01-21 .
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An archetype for mitigating the security threats in multi-cloud environment by implementing tree-based next-generation firewalls SCIE
期刊论文 | 2021 , 41 (1) , 125-136 | JOURNAL OF INTELLIGENT & FUZZY SYSTEMS
WoS核心集被引次数: 1
摘要&关键词 引用

摘要 :

Cloud computing on-demand dynamicity in nature of end-user that leads towards a hybrid cloud model deployment is called a multi-cloud. Multi-cloud is a multi-tenant and multi-vendor heterogeneous cloud platform in terms of services and security under a defined SLA (service level agreement). The diverse deployment of the multi-cloud model leads to rise in security risks. In this paper, we define a multi-cloud model with hybridization of vendor and security to increase the end-user experience. The proposed model has a heterogeneous cloud paradigm with a combination of firewall tracts to overcome rising security issues. The proposed work consists of three steps, firstly, all incoming traffic from the consumer end into five major groups called ambient. Secondly, design a next-generation firewall (NGFW) topology with a mixture of tree-based and demilitarized zone (DMZ) implications. Test implementation of designed topology performed by using a simple DMZ technique in case of vendor-specific model and NGFW on hybrid vendor based multi-cloud model. Furthermore, it also defines some advantages of NGFW to overcome these concerns. The proposed work is helpful for the new consumer to define their dynamic secure cloud services under a single SLA before adopting a multi-cloud platform. Finally, results are compared in terms of throughput and CPU utilization in both cases.

关键词 :

cloud computing cloud computing firewall security firewall security Multi-cloud Multi-cloud next-generation firewall (NGFW) next-generation firewall (NGFW) single SLA single SLA

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GB/T 7714 Hussain, Muhammad Iftikhar , He, Jingsha , Zhu, Nafei et al. An archetype for mitigating the security threats in multi-cloud environment by implementing tree-based next-generation firewalls [J]. | JOURNAL OF INTELLIGENT & FUZZY SYSTEMS , 2021 , 41 (1) : 125-136 .
MLA Hussain, Muhammad Iftikhar et al. "An archetype for mitigating the security threats in multi-cloud environment by implementing tree-based next-generation firewalls" . | JOURNAL OF INTELLIGENT & FUZZY SYSTEMS 41 . 1 (2021) : 125-136 .
APA Hussain, Muhammad Iftikhar , He, Jingsha , Zhu, Nafei , Zardari, Zulfiqar Ali , Razque, Fahad , Hussain, Saqib et al. An archetype for mitigating the security threats in multi-cloud environment by implementing tree-based next-generation firewalls . | JOURNAL OF INTELLIGENT & FUZZY SYSTEMS , 2021 , 41 (1) , 125-136 .
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A Highly Reliable Consensus Mechanism for Blockchain Based on Contribution and Difficulty Values EI
期刊论文 | 2021 , 44 (1) , 162-176 | Chinese Journal of Computers
摘要&关键词 引用

摘要 :

A consensus mechanism for blockchain based on proof of contribution (PoC) is a kind of consensus mechanism that is suitable for the application scenarios of intellectual property protection and transaction. In the PoC mechanism, the contribution values of user nodes are calculated periodically and the node with the largest contribution value will assume the right for the construction of a new block. However, the PoC consensus mechanism has the problem that the node that constructs the new block in the current round exhibits the property of strong certainty. If the node that is supposed to construct the new block in the current round fails to do so, all the other nodes will remain in the waiting state and the system will hang and execution can no longer continue. To make the PoC blockchain consensus mechanism applicable to the public chain scenario, this paper proposes a new consensus mechanism based on the contribution value as well as on the difficulty value in the proof of work consensus mechanism (PoC+PoW). In the PoC+PoW consensus mechanism, some uncertainty is added into the process of determining the right for the construction of a new block to overcome the shortcomings of the original PoC consensus mechanism. In PoC+PoW, the difficulty values of the mathematical problem that participating nodes try to solve in the PoW competition is dynamically determined according to the PoC values of the nodes. The proposed mechanism can thus be viewed as a disaster recovery scheme for the PoC consensus mechanism to ensure the reliability of the system operation. The proposed PoC+PoW consensus mechanism would allocate a corresponding PoW difficulty value to a node according to the ranking of the contribution value of the node. All nodes then compete for the right for bookkeeping and block construction through the PoW consensus mechanism. The new consensus mechanism that incorporates PoW would still fully respect the ranking of the contribution values from PoC to ensure that the probability of constructing a new block by a node is highly proportional to its ranking among all the contribution values. As far as system operation is concerned, the probability of block construction can be guaranteed to reach or approach infinitely to 100%, which should effectively solve the system hanging problem existing in PoC-based systems. This paper will present the design of an algorithm for the allocation of the PoW difficulty values from three aspects: the ranking of the contribution values, the difference between adjacent contribution values and the grouping method, and will verify the rationality and effectiveness of the proposed allocation algorithm through experiment. In addition, a comparison between the new PoC+PoW consensus mechanism and the traditional PoC consensus mechanism in terms of the efficiency of block construction further verifies the superiority and the feasibility of the proposed PoC+PoW consensus mechanism. © 2021, Science Press. All right reserved.

关键词 :

Blockchain Blockchain Software engineering Software engineering

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GB/T 7714 He, Jing-Sha , Zhang, Kun , Xue, Rui-Xin et al. A Highly Reliable Consensus Mechanism for Blockchain Based on Contribution and Difficulty Values [J]. | Chinese Journal of Computers , 2021 , 44 (1) : 162-176 .
MLA He, Jing-Sha et al. "A Highly Reliable Consensus Mechanism for Blockchain Based on Contribution and Difficulty Values" . | Chinese Journal of Computers 44 . 1 (2021) : 162-176 .
APA He, Jing-Sha , Zhang, Kun , Xue, Rui-Xin , Zhu, Na-Fei , He, Peng , Song, Hong-Yu et al. A Highly Reliable Consensus Mechanism for Blockchain Based on Contribution and Difficulty Values . | Chinese Journal of Computers , 2021 , 44 (1) , 162-176 .
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Security enhancement technologies for smart contracts in the blockchain: A survey SCIE
期刊论文 | 2021 | TRANSACTIONS ON EMERGING TELECOMMUNICATIONS TECHNOLOGIES
WoS核心集被引次数: 8
摘要&关键词 引用

摘要 :

Smart contract has shown its potential in cutting down the cost of administration through reshaping conventional business processes and in expanding the application of blockchain to areas that are beyond the cryptocurrency. However, with the rapid development and wide application of smart contracts, security issues have become a serious concern and have thus attracted widespread attention. As the result, a great deal of effort has been spent on improving and supporting secure development and on the application of smart contracts by introducing new and advanced vulnerability detection and privacy protection techniques in recent years. There is therefore the need for a comprehensive review of the new development on security enhancement technologies of smart contracts for the blockchain. This paper provides a review of the current research status and advances in smart contract security based on related literature published in recent years. Our review is divided into six categories along the line of the technology, which includes symbolic execution, abstract interpretation, fuzz testing, formal verification, deep learning, and privacy enhancement. A comparison of the various tools and methods developed to tackle security issues is provided. Challenges in the research of smart contract security as well as future directions are discussed. This paper intends to provide the inspiration and reference for follow-up research on the security issues of smart contracts in the blockchain.

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GB/T 7714 Wang, Yajing , He, Jingsha , Zhu, Nafei et al. Security enhancement technologies for smart contracts in the blockchain: A survey [J]. | TRANSACTIONS ON EMERGING TELECOMMUNICATIONS TECHNOLOGIES , 2021 .
MLA Wang, Yajing et al. "Security enhancement technologies for smart contracts in the blockchain: A survey" . | TRANSACTIONS ON EMERGING TELECOMMUNICATIONS TECHNOLOGIES (2021) .
APA Wang, Yajing , He, Jingsha , Zhu, Nafei , Yi, Yuzi , Zhang, Qingqing , Song, Hongyu et al. Security enhancement technologies for smart contracts in the blockchain: A survey . | TRANSACTIONS ON EMERGING TELECOMMUNICATIONS TECHNOLOGIES , 2021 .
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A cost-effective adaptive random testing algorithm for object-oriented software testing SCIE
期刊论文 | 2021 , 41 (3) , 4415-4423 | JOURNAL OF INTELLIGENT & FUZZY SYSTEMS
WoS核心集被引次数: 1
摘要&关键词 引用

摘要 :

The rapid development of object oriented programming (OOP) technology has made it one of the mainstream programming technologies that has been widely used in the design and development of object oriented software (OOS). The inheritance, encapsulation and polymorphism properties of object-oriented language can improve the reusability, scalability and interoperability of software while increasing the difficulty of testing OOS. Researchers have proposed a variety of testing methods to test OOS among which random testing (RT) has been widely used due to its simplicity and ease of use. An OMISS-ARTsum algorithm is proposed in this paper that uses improved OMISS random test FSCS-ART with max-sum standard, which is an implementation version of fixed-sized-candidate-set ART. The OMISS-ARTsum algorithm calculates the total distance between a candidate test case and the executed test case set before the next test case is selected from the set of candidate test cases. Unlike the traditional max-sum based FSCS-ART algorithm, OMIS S-ARTsum does not calculate the distance between each executed test case and the candidate case and then sum up the total distance, but uses the method of summing up all the executed test cases and the candidate cases. The information of executing test cases is saved as a whole and the distance between the executed test case set and candidate cases is calculated at the same time. Experiment shows that compared to the OMISS-ART algorithm, the proposed OMISS-ARTsum algorithm can reduce the time overhead.

关键词 :

adaptive random testing adaptive random testing Object oriented software Object oriented software test input test input time cost time cost

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GB/T 7714 Zhou, Yue , Wang, Xiujun , Guo, Shu et al. A cost-effective adaptive random testing algorithm for object-oriented software testing [J]. | JOURNAL OF INTELLIGENT & FUZZY SYSTEMS , 2021 , 41 (3) : 4415-4423 .
MLA Zhou, Yue et al. "A cost-effective adaptive random testing algorithm for object-oriented software testing" . | JOURNAL OF INTELLIGENT & FUZZY SYSTEMS 41 . 3 (2021) : 4415-4423 .
APA Zhou, Yue , Wang, Xiujun , Guo, Shu , Wen, Yi , He, Jingsha . A cost-effective adaptive random testing algorithm for object-oriented software testing . | JOURNAL OF INTELLIGENT & FUZZY SYSTEMS , 2021 , 41 (3) , 4415-4423 .
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Proof-of-Contribution consensus mechanism for blockchain and its application in intellectual property protection EI
期刊论文 | 2021 , 58 (3) | Information Processing and Management
摘要&关键词 引用

摘要 :

Blockchain has received a lot of attention recently for its characteristics of decentralization, immutability, traceability, etc., making it a promising technology for the development of various applications, especially the management of various digital information. However, most current blockchain systems exhibit problems such as high computational overhead and centralization of power. Reliance on cryptocurrency in many public blockchain-based applications is another factor that has hindered the application of blockchain technology in areas other than the financial sectors. This paper proposes a new blockchain consensus mechanism based on the contributions of participants. The proposed consensus mechanism, which is called proof-of-contribution (PoC), quantifies user behaviors and actions in a blockchain-based application as contribution values calculated through an algorithm. The node that has the highest contribution value in each round of consensus gets the right to generate the next new block. PoC preserves the properties of decentralization and resistance to hard fork and does not rely on cryptocurrency, making it attractive over cryptocurrency-based consensus mechanisms like proof-of-work (PoW) for a wide variety of applications that do not have to involve cryptocurrency. Contribution values can be abstracted from applications and used in the underlying blockchain consensus process to improve the security and trustworthiness of the applications. Intellectual property (IP) protection is one such application to apply the blockchain technology and the PoC consensus mechanism. However, existing blockchain-based IP protection systems are mostly developed based on public blockchain platforms such as the Ethereum while some others are developed as consortium blockchains, thus exhibiting inherent defects such as high system requirements, long consensus delay, and low user participation. In this paper, we will use IP protection as the application scenario to illustrate the development of our PoC consensus mechanism and will compare PoC to some existing consensus mechanisms. Experimental results will show that the proposed PoC consensus mechanism preserves most of the main security characteristics of blockchain and is superior to existing consensus mechanisms, making it more secure and efficient to use blockchain technology for digital information management. © 2021 Elsevier Ltd

关键词 :

Behavioral research Behavioral research Blockchain Blockchain Cryptocurrency Cryptocurrency Information management Information management Intellectual property Intellectual property Network security Network security

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GB/T 7714 Song, Hongyu , Zhu, Nafei , Xue, Ruixin et al. Proof-of-Contribution consensus mechanism for blockchain and its application in intellectual property protection [J]. | Information Processing and Management , 2021 , 58 (3) .
MLA Song, Hongyu et al. "Proof-of-Contribution consensus mechanism for blockchain and its application in intellectual property protection" . | Information Processing and Management 58 . 3 (2021) .
APA Song, Hongyu , Zhu, Nafei , Xue, Ruixin , He, Jingsha , Zhang, Kun , Wang, Jianyu . Proof-of-Contribution consensus mechanism for blockchain and its application in intellectual property protection . | Information Processing and Management , 2021 , 58 (3) .
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