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1.
Stream ciphers based on linear feedback shift register (LFSR) are suitable for constrained environments, such as satellite communications, radio frequency identification devices tag, sensor networks and Internet of Things, due to its simple hardware structures, high speed encryption and lower power consumption. LFSR, as a cryptographic primitive, has been used to generate a maximum period sequence. Because the switching of the status bits is regular, the power consumption of the LFSR is correlated in a linear way. As a result, the power consumption characteristics of stream cipher based on LFSR are vulnerable to leaking initialization vectors under the power attacks. In this paper, a new design of LFSR against power attacks is proposed. The power consumption characteristics of LFSR can be masked by using an additional LFSR and confused by adding a new filter Boolean function and a flip-flop. The design method has been implemented easily by circuits in this new design in comparison with the others. 相似文献
2.
CRAFT is a tweakable block cipher introduced in 2019 that aims to provide strong protection against differential fault analysis. In this paper, we show that CRAFT is vulnerable to side-channel cube attacks. We apply side-channel cube attacks to CRAFT with the Hamming weight leakage assumption. We found that the first half of the secret key can be recovered from the Hamming weight leakage after the first round. Next, using the recovered key bits, we continue our attack to recover the second half of the secret key. We show that the set of equations that are solvable varies depending on the value of the key bits. Our result shows that 99.90% of the key space can be fully recovered within a practical time. 相似文献
3.
Bahram Rashidi 《International Journal of Circuit Theory and Applications》2020,48(8):1227-1243
In this paper, low-cost and two-cycle hardware structures of the PRINCE lightweight block cipher are presented. In the first structure, we proposed an area-constrained structure, and in the second structure, a high-speed implementation of the PRINCE cipher is presented. The substitution box (S-box) and the inverse of S-box (S-box−1) blocks are the most complex blocks in the PRINCE cipher. These blocks are designed by an efficient structure with low critical path delay. In the low-cost structure, the S-boxes and S-boxes−1 are shared between the round computations and the intermediate step of PRINCE cipher. Therefore, the proposed architecture is implemented based on the lowest number of computation resources. The two-cycle implementation of PRINCE cipher is designed by a processing element (PE), which is a general and reconfigurable element. This structure has a regular form with the minimum number of the control signal. Implementation results of the proposed structures in 180-nm CMOS technology and Virtex-4 and Virtex-6 FPGA families are achieved. The proposed structures, based on the results, have better critical path delay and throughput compared with other's related works. 相似文献
4.
Edon80 is a stream cipher design that had advanced to the third and last phase of the eSTREAM project. The core of the cipher consists quasigroup string e-transformations and it employs four quasigroups of order 4. The employed quasigroups have influence on the period of the keystream. There are 576 quasigroups of order 4 in total which have different period factors. The four quasigroups used in Edon80 were chosen by numerous computer experiments. In this paper, based on permutation groups, we give a theory criterion for the determination of quasigroups and give a complete classification for the 576 quasigroups of order 4 according to their period factors. 相似文献
5.
分析了国内外物联网安全政策、技术、标准、产业等形势,重点强调了当前我国物联网发展中存在的安全风险,包括大连接环境下的设备风险、物联网网络本身安全风险以及物联网上承载的各类应用安全风险,提出了打造以密码为核心的物联网安全体系,加速新技术在物联网安全的应用,以新基建为契机建立物联网领域安全设备泛在化部署新体系,以多层次立体式理念确保物联网安全,呼吁供给侧需求侧建立安全协同新机制,共同促进物联网产业安全可持续发展。 相似文献
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7.
介绍了用ObjectARX对AutoCAD进行三维开发的方法,利用圆锥面近似替代螺旋面的画法,较好地形成了螺纹的结构,并编程实现了螺纹实体的参数化绘图。这种方法对绘制其他牙型的螺纹实体结构,具有指导意义。 相似文献
8.
9.
有限元前后处理系统的开发对工程设计和分析具有重要的意义。本文采用先进的ObjectARX技术,结合大跨度桥梁抗震设计的需要开发了适合大跨度桥梁抗震设计建模和数据处理的有限元前后处理系统。 相似文献
10.
The frequencies of n-graphs, groups of n letters, for n as large as 6 are compiled and used to launch a statistical attack on a running key cipher. Programs written in C++ make the calculations possible. The results of the attack for various values of n are analyzed. 相似文献