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RAINBOW分组密码的线性密码分析 总被引:1,自引:0,他引:1
本文在对RAINBOW分组密码的基础模块深入研究和测试后,利用扩散层的特点,对RAINBOW分组密码进行了线性密码分析,攻击的数据复杂度为294,计算复杂度小于218.此结果显示RAINBOW分组密码对线性密码分析是不免疫的. 相似文献
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2004年与2005年是中国密码学界值得自豪的两年,一直在国际上广泛应用的两大密码算法MD5、SHA—1,宣布被中国密码专家破解,一时间国际密码学领域风起云涌.MD5与SHA—1算法是目前国际电子签名及许多其他密码应用领域的关键技术,广泛应用于金融、证券等电子商务领域.其中,SHA—1算法早在1994年便为美国政府采纳,目前广泛应用于美国政府的计算机密码系统.以往,专家们认为这两个算法固若金汤,哪怕调用全球的计算机,花费数百年、上千年的时间,也难以破解这两个算法.但这一切在2004年8月之后改变了:中国人攻克了这两座堡垒.破解这两大国际通… 相似文献
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把近似熵用于密码技术中,设计一种实用的随机数检验方法.该方法可以检测随机序列发生器产生序列的随机性,也可以用于检验密码算法的安全性.通过实验,发现该方法能更全面检验序列的随机特性. 相似文献
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本文研究了带二次耦合项的二维Logistic映射的性质和分岔行为,数值模拟了混沌的生成过程.若控制一个参数值近似为1,则产生近乎满的混沌区.这种混沌区产生的随机序列所生成的流密码具有很好的0-1分布、高线性复杂性、密钥敏感性等.最后给出了用于保密通信的模型. 相似文献
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Yanbing Liu Simei TianWenping Hu Congcong Xing 《Communications in Nonlinear Science & Numerical Simulation》2012,17(8):3267-3278
Security issue is a vital and active topic in the research of Wireless Sensor Networks (WSN). After surveying the existing encryption algorithms for WSN briefly, we propose a new chaotic block cipher for WSN and then compare the performance of this cipher with those of RC5 and RC6 block ciphers. Simulation result demonstrates that better performance in WSN encryption algorithms can be achieved using the new cipher. 相似文献
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Alasdair McAndrew 《International Journal of Mathematical Education in Science & Technology》2013,44(7):967-979
The Hill cipher is the simplest example of a block cipher, which takes a block of plaintext as input, and returns a block of ciphertext as output. Although it is insecure by modern standards, its simplicity means that it is well suited for the teaching of such concepts as encryption modes, and properties of cryptographic hash functions. Although these topics are central to modern cryptography, it is hard to find good simple examples of their use. The conceptual and computational simplicity of the Hill cipher means that students can experiment with these topics, see them in action, and obtain a better understanding that would be possible from a theoretical discussion alone. In this article, we define the Hill cipher and demonstrate its use with different modes of encryption, and also show how cryptographic hash functions can be both designed and broken. Finally, we look at some pedagogical considerations. 相似文献
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Ping Li Zhong Li Wolfgang A. Halang Guanrong Chen 《Chaos, solitons, and fractals》2007,32(5):1867-1876
A stream cipher based on a spatiotemporal chaotic system is proposed. A one-way coupled map lattice consisting of logistic maps is served as the spatiotemporal chaotic system. Multiple keystreams are generated from the coupled map lattice by using simple algebraic computations, and then are used to encrypt plaintext via bitwise XOR. These make the cipher rather simple and efficient. Numerical investigation shows that the cryptographic properties of the generated keystream are satisfactory. The cipher seems to have higher security, higher efficiency and lower computation expense than the stream cipher based on a spatiotemporal chaotic system proposed recently. 相似文献
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量子Grover算法及其应用 总被引:3,自引:1,他引:2
杜治国 《数学的实践与认识》2006,36(6):313-317
深入剖析了G rover算法,最后将其应用于经典密码学,对序列密码和分组密码等进行了攻击和分析. 相似文献
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《Communications in Nonlinear Science & Numerical Simulation》2014,19(4):905-913
Self-synchronizing stream cipher (SSSC) has the advantage that the receiver can automatically synchronize with the sender after receiving previously transmitted ciphertext. However, it has also serious difficulty to keep security due to its self-synchronizing structure. In this paper, a new SSSC based on one-way coupled chaotic map lattice is proposed. By combining floating-point chaotic computations with algebraic operations, the cipher has high bit confusion and diffusion rates. It has both advantages of robustness of synchronization and strong security. The cipher can serve as a new type of SSSC candidate in software implementation. 相似文献
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In threshold cryptography, the goal is to distribute the computation of basic cryptographic primitives across a number of nodes in order to relax trust assumptions on individual nodes, as well as to introduce a level of fault-tolerance against node compromise. Most threshold cryptography has previously looked at the distribution of public key primitives, particularly threshold signatures and threshold decryption mechanisms. In this paper, we look at the application of threshold cryptography to symmetric primitives, and in particular the encryption or decryption of a symmetric key block cipher. We comment on some previous work in this area and then propose a model for shared encryption / decryption of a block cipher. We will present several approaches to enable such systems and will compare them.AMS classification: 94A60, 94A62, 68P25 相似文献
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Biryukov (The Design of a Stream Cipher LEX, Proceedings of Selected Areas in Cryptography, 2006 Springer, pp 67–75, 2007) presented a new methodology of stream cipher design called leak extraction. The stream cipher LEX, based on this methodology and on the AES block cipher, was selected to round 3 of the eSTREAM competition. The suggested methodology seemed promising, and LEX, due to its elegance, simplicity, and performance, was expected to be selected to the eSTREAM portfolio. In this article we present a key recovery attack on LEX. The attack requires about 240 bytes of key-stream produced by the same key (possibly under many different IVs), and retrieves the secret key in time of about 2100 AES encryptions. Following a preliminary version of our attack, LEX was discarded from the final portfolio of eSTREAM. 相似文献
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Andreas Klein 《Designs, Codes and Cryptography》2008,48(3):269-286
In this article we present some weaknesses in the RC4 cipher and their cryptographic applications. Especially we improve the
attack described by Fluhrer, Mantin, Shamir (In: Selected Areas in Cryptography, 2001) in such a way, that it will work, if
the weak keys described in that paper are avoided. A further attack will work even if the first 256 Byte of the output remain
unused. Finally we show that variants of the RC4 algorithm like NGG and RC4A are also vulnerable by these techniques.
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