With the rapid development of cloud storage and cloud computing technology, users tend to store data in the cloud for more convenient services. In order to ensure the integrity of cloud data, scholars have proposed cloud data integrity verification schemes to protect users' data security. The storage environment of the Internet of Things, in terms of big data and medical big data, demonstrates a stronger demand for data integrity verification schemes, but at the same time, the comprehensive function of data integrity verification schemes is required to be higher. Existing data integrity verification schemes are mostly applied in the cloud storage environment but cannot successfully be applied to the environment of the Internet of Things in the context of big data storage and medical big data storage. To solve this problem when combined with the characteristics and requirements of Internet of Things data storage and medical data storage, we designed an SM2-based offline/online efficient data integrity verification scheme. The resulting scheme uses the SM4 block cryptography algorithm to protect the privacy of the data content and uses a dynamic hash table to realize the dynamic updating of data. Based on the SM2 signature algorithm, the scheme can also realize offline tag generation and batch audits, reducing the computational burden of users. In security proof and efficiency analysis, the scheme has proven to be safe and efficient and can be used in a variety of application scenarios.

为解决好专业教育和思政教育"两张皮"问题,落实立德树人根本任务,结合信息安全专业特色、计算机网络教学内容及学情分析,提出"情智交融"的思政教学设计思路,沿循"挖掘—优化—促进—反哺"路径最终达成培养目标,阐述如何结合教学内容深挖思政元素,并以ARP教学内容为例,介绍计算机网络课程思政教学实践.

针对密码学与信息安全专业毕业生实战能力普遍偏弱的问题,瞄准"高素质信息安全人才实战能力培育"这一体系,以构建信息安全实战能力培育体系为核心,以解决当前教学训练环境的靶向性和实效性不够的问题为主线,围绕仿真环境的创新性设计、仿真平台的体系化构建、实训条件的科学性运用等方面,提出"一体两翼四驱"的实战化模拟仿真教学环境设计模式,并对其建设与运用情况进行分析.

Cloud storage technology is evolving at a high speed; effectively auditing the cloud data’s integrity has become a focal point. Recently, Ming and Shi proposed a certificateless integrity auditing scheme with a privacy protection function. The scheme used the certificateless cryptosystem to solve the certificate management problem of the auditing schemes based on public key infrastructure and the key escrow problem of the identity-based auditing schemes. Although their scheme is novel and efficient, we found that their scheme was not secure and could not achieve integrity auditing of cloud data. The malicious cloud server can generate the proof through the blocks and tags sent by the user. On the basis of the original scheme, we propose an improved auditing scheme; our new scheme is more secure and effective. In addition, for the problem of idle tags in the existing cloud data integrity auditing scheme, we propose the idea of intermediate tags and we applied the idea to the improved scheme to improve audit efficiency.

In order to solve the problem of low audit efficiency due to the use of power exponent, bilinear mapping, point hash mapping and other expensive operations in the existing certificateless cloud auditing scheme, an efficient certificateless cloud auditing scheme was designed in this paper. In the key generation stage, combined with the certificateless signature technology, the user’s public and private keys were generated by the key generating center (KGC) in cooperation with the user, so that the strong dependence of auditing system security on KGC security was avoided. Consequently, the shortcomings of complex public key certificate management under the public key infrastructure (PKI) system and the inherent key escrow issues under the identity-based cloud audit scheme were solved. In the data preprocessing stage, the data was encrypted and divided into blocks. Therefore, the data content privacy was protected and the calculation and communication overhead of the scheme was reduced. In the data dynamic update stage, the virtual index data structure was used to realize the insertion, deletion and modification of data blocks. As a result, the extra computational overhead caused by label recalculation was avoided. In the data auditing stage, the task of users to verify the integrity evidence was replaced by a third party auditor (TPA), which reduces the user’s computational burden. In the section of security analysis, it was proved that the substitution attack from the cloud was resisted, the privacy protection was achieved, and the forgery attacks by two types of adversaries were resisted. In the performance analysis part, numerical analysis and comparison of the proposed scheme with the existing schemes were carried out on the JPBC library. The experiments show that the proposed scheme significantly reduces the computational cost.

针对现有无证书云审计方案中,使用了幂指数、双线性映射、点哈希映射等大开销运算,导致审计效率不高的问题,本文提出一种高效的无证书云数据完整性验证方案.方案在密钥生成阶段,使用无证书签名技术,由密钥生成中心(key generating center,KGC)与用户合作生成用户的公私钥,能够避免审计系统的安全对于KGC安全的强依赖性,既解决了公钥基础设施(public key infrastructure,PKI)体制下的云审计方案中公钥证书管理复杂的缺点,又能够解决基于身份的云审计方案所固有的密钥托管问题.在数据预处理阶段,用户将数据加密、分块,保护了数据内容隐私,且降低了方案的计算与通信开销.在数据动态更新阶段,方案使用虚拟索引数据结构实现云端数据块的动态更新(插入、删除、修改),能够避免标签重复计算导致的额外计算开销.在数据审计阶段,由第三方审计者(third party auditor,TPA)代替用户对来自云端的完整性证据进行验证,能够减轻用户的计算负担.本文在安全性分析部分,证明了方案能够抵抗来自云端的替代攻击,可实现隐私保护,且能够抵抗两类敌手的伪造攻击.在方案性能分析部分,先对本方案和现有方案进行数值分析与对比,再利用JPBC库进行实验,结果表明本方案的计算开销明显降低.

针对云审计中第三方审计机构(TPA)可能存在的恶意欺骗行为,提出一种无双线性对的、能够正确检查TPA行为的可信云审计方案.首先,利用伪随机比特生成器生成随机挑战信息,以保证TPA生成挑战信息可靠;其次,在证据生成过程中增加哈希值,从而有效保护用户数据隐私;然后,在证据验证过程中,增加用户和TPA结果的交互过程,根据这个结果检查数据完整性,并判断TPA是否如实完成审计请求;最后,扩展该方案以实现多项数据的批量审计.安全分析表明,所提方案能够抵抗替换攻击和伪造攻击,且能保护数据隐私.相比基于Merkle哈希树的无双线性对(MHT-WiBPA)审计方案,所提方案的验证证据时间接近,而标签生成时间降低约49.96％.效能分析表明,所提方案在保证审计结果可信的前提下,实现了更低的计算开销和通信开销.

加强实践教学、提升实践能力是当前院校教学改革的重点.文章分别从教学目标模型构建、教学内容体系优化、教学实施规范创新、教学模式方法改革、一体化改革实践5个方面阐述信息安全专业实践教学改革与创新的实施办法,目的是为提高信息安全人才培养质量提供参考和借鉴.

With the rapid development of mobile smartphone and its built-in location-aware devices, people are possible to establish trust relationships and further interaction with each other based their matched interests, hobbies, experiences, or spatiotemporal profiles. However, the possibility of sensitive information leakage and heavy computation overhead constrain the widespread use of the matching schemes in mobile social networks. Many privacy-preserving matching schemes were proposed recently years, but how to achieve privacy-preserving spatiotemporal matching exactly and efficiently remains an open question. In this paper, the authors propose a novel spatiotemporal matching scheme. The overlapping grid system is introduced into the scheme to improve the accuracy of spatiotemporal matching, and many repetitive records in a user's spatiotemporal profile are counted as one item so as to cut down the computation overhead. Their scheme decreases the spatiotemporal matching error, and promotes the efficiency of private matchmaking simultaneously. Thorough security analysis and evaluation results indicate that our scheme is effective and efficient.

We propose an exactly spatiotemporal matching scheme for privacy-aware users in MSNs. Based on the carefully designed spatiotemporal profile, our scheme employs a weight-aware pre-matching module to filter out the users with less similarity and some potential adversaries, thus guarantees that no useful information is revealed before determining the best matches. Further, we propose a privacy-preserving exchanging module against Honest-But-Curious users. Finally, the similarity computing module computes the exact matching result to each candidate to determine the best match. Thorough security analysis and evaluation results indicate the effectiveness and efficiency.

With the rapid popularization of mobile smartphone and its built-in location-aware devices, people are possible to establish trust relationships with each other by matching their interests, hobbies, experiences, or spatiotemporal profiles. However, the contradiction between the possibility of personal sensitive information leaking and the growing privacy concerns of users restricts the widespread use of direct matching schemes. To addressthis problem, lots of privacy-preserving matching schemes were proposed recently years. These schemes ensure users find the perfect matcher(s) without revealing extra unnecessary personal information. And yet, at the same time, it is inevitable that they produce more computation amount and communication traffic compare with former direct matching schemes. For mobile application scenarios, it is a heavy burden since power is limited. Particularly, for spatiotemporal matching, the situation is much worse due to the number of elements in users' spatiotemporal profiles will be very large as time goes on. Another outstanding issue in spatiotemporal matching is that how to define two users are neighboring. So, how to achieve an efficient and exactly privacy-preserving spatiotemporal matching remains an open question. In this paper, we propose a fine-grained privacypreserving spatiotemporal matching in Mobile Social Networks. Our scheme decreases the spatiotemporal matching error, as well as promotes the efficiency of matchmaking. Thorough security analysis and evaluation results indicate that our scheme is effective and efficient.

With the advent of the era of big data, the data scale being processed is more and more large, which brings new challenge to the design of privacy-preserving protocols. For the Private Set Intersection (PSI) problem, when the sizes of sets is large, keeping its efficiency and scalability is becoming very difficult. In addition, elements in these sets are likely to be twodimensional data, which usually contains an attribute and its corresponding weight. That increases the difficulty to solve the problem. Some creative protocols were proposed to settle the PSI problem recently. However, these protocols can only protect the privacy of the one-dimension elements of users' private sets. And when the elements are two-dimensional, they are not work. In this paper, we propose an efficient and scalable protocol for sets which have two-dimensional elements. Thorough security analysis indicate that our scheme is effective and efficient.

Micro-arc oxidation films were prepared on magnesium alloy AZ91D in a aluminate electrolyte.The effects of electric parameters during the micro-arc oxidation process on properties of MAO films were systematically investigated using the Taguchi experimental analysis method.The optimized parameters are 180 V voltage,30 min oxidation time,50 Hz frequency,30% duty cycle.The corrosion resistance of the MAO film was examined by means of AC impedance.The results show that the resistance of MAO film treated on optimized conditions increase by two orders compared with the magnesium alloy substrate.This enhances the corrosion resistance of the magnesium alloy.

A new watermarking algorithm resisting to geometric transformation based on singular value decomposition (SVD) in logarithm polar coordinate is proposed. The log-polar mapping (LPM) is used to resist rotation and scaling attacks, and the odd-even quantization algorithm is used to embed watermark so it can be extracted without the original host image. The experiments show that the proposed algorithm not only resists various geometric attacks but also is robust enough to the common signal processing.

The contingency screen is one of the important module of online dynamic security assessmentThe function of contingency screen is to pick up the serious contingencies of which predefined and it can greatly reduced the quantity of the contingencies to be analysis.In this paper a method of contingency screen which is Neural Network optimized based on MEC is put forward,and the effection of this method is proved with 10-generator 39-bus system.

Based on Mind Evolutionary Computation, this paper presents a diagnosis model of transformer faults used in the gas dissolved in transformer oil. With dissolved gas content in transformer oil as input parameters, the method can get corresponding relationship between input and output parameters according to the principle of similartaxis and dissimilation, Analysis shows that the method used for transformer fault diagnosis is effective.