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1.
In this paper, we first re-examine the previous protocol of controlled quantum secure direct communication of Zhang et al.’s scheme, which was found insecure under two kinds of attacks, fake entangled particles attack and disentanglement attack. Then, by changing the party of the preparation of cluster states and using unitary operations, we present an improved protocol which can avoid these two kinds of attacks. Moreover, the protocol is proposed using the three-qubit partially entangled set of states. It is more efficient by only using three particles rather than four or even more to transmit one bit secret information. Given our using state is much easier to prepare for multiqubit states and our protocol needs less measurement resource, it makes this protocol more convenient from an applied point of view.  相似文献   
2.
As an Industrial Wireless Sensor Network (IWSN) is usually deployed in a harsh or unattended environment, the privacy security of data aggregation is facing more and more challenges. Currently, the data aggregation protocols mainly focus on improving the efficiency of data transmitting and aggregating, alternately, the aim at enhancing the security of data. The performances of the secure data aggregation protocols are the trade-off of several metrics, which involves the transmission/fusion, the energy efficiency and the security in Wireless Sensor Network (WSN). Unfortunately, there is no paper in systematic analysis about the performance of the secure data aggregation protocols whether in IWSN or in WSN. In consideration of IWSN, we firstly review the security requirements and techniques in WSN data aggregation in this paper. Then, we give a holistic overview of the classical secure data aggregation protocols, which are divided into three categories: hop-by-hop encrypted data aggregation, end-to-end encrypted data aggregation and unencrypted secure data aggregation. Along this way, combining with the characteristics of industrial applications, we analyze the pros and cons of the existing security schemes in each category qualitatively, and realize that the security and the energy efficiency are suitable for IWSN. Finally, we make the conclusion about the techniques and approach in these categories, and highlight the future research directions of privacy preserving data aggregation in IWSN.  相似文献   
3.
量子时域鬼成像利用光子对的时间-频率关联性实现了50km光纤链路上的图像传送,有望应用于量子通信的协议中。然而,现有方案的成像质量较差,成像速度较慢,因此其应用性在一定程度上受到了限制。文章对已有成像方案进行了较大的改进,利用可编程滤波器数字设定待成像信息,进而实现了二维图像信息的自动化实时传送。实验结果证明,改进方案的成像质量和速度均有显著改善,有利于推动量子关联成像在量子通信领域的应用。  相似文献   
4.
智能感知技术是数字化的关键技术之一,是能源互联网的基础技术。在当前数字化进程深入推动能源革命的背景下,智能感知技术已成为能源互联网建设与发展的数字引擎。文章总结了能源互联网框架下智能感知技术的战略背景、业务需求及重要意义,通过分析当前存在的问题,详细阐述了智能感知技术理论及发展趋势,梳理智能感知核心技术框架,提出系统性技术标准体系,并给出了能源互联网“源-网-荷-储”智能感知应用布局,最后结合我国能源互联网发展现状,对智能感知建设路径与发展方向进行了探讨与展望。  相似文献   
5.
Oblivious polynomial evaluation (OPE) is a two-party protocol that allows a receiver, R to learn an evaluation f(α), of a sender, S's polynomial f(x), whilst keeping both α and f(x) private. This protocol has attracted a lot of attention recently, as it has wide ranging applications in the field of cryptography. In this article we review some of these applications and, additionally, take an in-depth look at the special case of information theoretic OPE. Specifically, we provide a current and critical review of the existing information theoretic OPE protocols in the literature. We divide these protocols into two distinct cases (three-party and distributed OPE) allowing for the easy distinction and classification of future information theoretic OPE protocols. In addition to this work, we also develop several modifications and extensions to existing schemes, resulting in increased security, flexibility and efficiency. Lastly, we also identify a security flaw in a previously published OPE scheme.  相似文献   
6.
López-Alt et al.(STOC12)put forward a primitive called multi-key fully homomorphic encryption(MKFHE),in which each involved party encrypts their own data using keys that are independently and randomly chosen whereby arbitrary computations can be performed on these encrypted data by a final collector.Subsequently,several superior schemes based on the standard assumption(LWE)were proposed.Most of these schemes were constructed by expanding a fresh GSW-ciphertext or BGV-ciphertext under a single key to a new same-type ciphertext of the same message under a combination of associated parties’keys.Therefore,the new ciphertext’s size grew more or less linearly with an increase in the number of parties.In this paper,we proposed a novel and simple scheme of MKFHE based on LWE without increasing the size of the ciphertext in the two non-collusion server model.In other words,each party first independently shares their own data between two servers and each server only needs a one-round communication with another to construct a ciphertext of the same plaintext under a sum of associated parties’keys.Our new ciphertext under multiple keys has the same size as that of the original one with only one-round communication between two servers.The communication complexity is O(kmlogq)-bit,where k is the number of input ciphertexts involved,m is the size of a GSW-ciphertext and q is a modulus.In conclusion,we proved that our scheme is CPA-secure against semi-honest adversaries.  相似文献   
7.
郑文甫 《包钢科技》2006,32(6):76-78
文中从企业文化的概念、内容、结构及建设安全文化的目的、意义等入手进行分析,提出加强企业安全文化建设的建议.从而说明企业安全文化一旦形成,安全制度将不再是一种强制规章,而变为一种精神,一种道德,一种增强企业竞争力的文化动力.  相似文献   
8.
目前智能变电站系统安全防护主要依据IEC 62351标准实施,IEC 62351是国际标准,其涉及的安全技术主要采用国际算法RSA、AES及数字证书。针对智能变电站系统通信存在的安全缺陷,本文提出以下3方面解决方案,1)提出基于IEC 62351安全机制的智能变电站设备间通信采用国密算法与调度数字证书技术;2)发现调度主站到变电站通信协议IEC 104的安全隐患,提出安全改造方案及实现方法;3)提出站控层与过程层通信协议改造方案并采用国密算法与调度证书技术实现。通过采取以上安全措施,确保站内通信信息以及信息资源的实时性、可靠性、保密性、完整性和可用性,杜绝未授权用户的非法接入,保证通信双方身份的真实性及业务数据的可追溯性。  相似文献   
9.
This paper proposes a chaotic map‐based multicast scheme for multiuser speech wireless communication and implements it in an ARM platform. The scheme compresses the digital audio signal decoded by a sound card and then encrypts it with a three‐level chaotic encryption scheme. First, the position of every bit of the compressed data is permuted randomly with a pseudo‐random number sequence (PRNS) generated by a 6‐D chaotic map. Then, the obtained data are further permuted in the level of byte with a PRNS generated by a 7‐D chaotic map. Finally, it is operated with a multiround chaotic stream cipher. The whole system owns the following merits: the redundancy in the original audio file is reduced effectively and the corresponding unicity distance is increased; the balancing point between a high security level of the system and real‐time conduction speed is achieved well. In the ARM implementation, the framework of communication of multicast–multiuser in a subnet and the Internet Group Manage Protocol is adopted to obtain the function of communication between one client and other ones. Comprehensive test results were provided to show the feasibility and security performance of the whole system. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
10.
Unlike debates about security for owner occupiers which recognise that security is complex and multi-layered, security for renters is often presented as single dimensional and conflated with de jure security of tenure, deriving from a property rights perspective. This article proposes a broader concept of ‘secure occupancy’ to enable a more nuanced understanding of security for tenants. A new framework is developed to enable investigation of the dynamic interactions between legislation/regulation, housing market conditions, public policies and cultural norms around renting, which shape security of occupancy for tenants. The paper illustrates this approach, drawing on a study of the rental systems of nine developed countries, identifying key factors that appear to have a strong bearing on strengthening, and weakening, of security of occupancy for renter households. The article concludes that this approach has the potential to deepen understanding of security for renters and to stimulate new avenues for research.  相似文献   
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