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71.
72.
后向攻击技术方案的对比与选择 总被引:4,自引:1,他引:3
以空战前向攻击为参照,以对比的方式分析,论证了导弹越肩发射后向攻击和后向发射后向攻击技术方案的特点和存在的问题,在此讨论的基础上,提出了选择空战导弹后向攻击技术方案的倾向性意见。 相似文献
73.
For the most compelling applications of threshold cryptosystems, security against chosen cipher text attack is a requirement.
However, prior to the results presented here, there appeared to be no practical threshold cryptosystems in the literature
that were provably chosen ciphertext secure, even in the idealized random oracle model. The contribution of this paper is
to present two very practical threshold cryptosystems, and to prove that they are secure against chosen ciphertext attack
in the random oracle model. Not only are these protocols computationally very efficient, but they are also non-interactive,
which means they can be easily run over an asynchronous communication network.
Received November 2000 and revised September 2001 Online publication 11 March 2002 相似文献
74.
A statistical approach to cryptanalysis of a memoryless function of clock-controlled shift registers is introduced. In the case of zero-order correlation immunity, an algorithm for a shift register initial state reconstruction based on the sequence comparison concept is proposed. A constrained Levenshtein distance relevant for the cryptanalysis is defined and a novel recursive procedure for its efficient computation is derived. Preliminary experimental results are given and open theoretic problems are discussed.Following [11], a Boolean function f(x
1,..., x
n) is said to be mth-order correlation immune if m is the maximum integer such that the random variable f(X
1,..., X
n) is statistically independent of every set of m random variables chosen from the balanced and independent binary random variables X
1,..., X
n. 相似文献
75.
76.
针对现在空战中指挥系统与攻击系统的数据融合存在的不足,给出了经过改进后的现代空战指挥系统及攻击系统流程图及原理;介绍了攻击系统中的火控解算原理并进行了分析和优化计算,为完善现代空战指挥及攻击系统理论提供了一定依据;同时对战术决策及逻辑攻击有一定的指导作用。 相似文献
77.
针对传统的ElGamal加密机制不能抵抗自主选择密文攻击的问题,通过引入安全Hash函数和伪随机数发生函数给出了一种新的增强ElGamal加密机制.结果表明,该机制不仅能够抵抗自主选择密文攻击,且由于伪随机数发生函数的引入,解决了加密过程中随机数的暴露问题.该机制加密过程需要两次模幂运算,解密过程仅需一次模幂运算.完全适合于对安全性要求较高但是对系统资源要求消耗低的应用环境. 相似文献
78.
利用集合知识构造认证码 总被引:1,自引:0,他引:1
本文利用集合知识构造认证码,使其r(r>0)阶欺骗攻击成功的概率pr达到文献[2]的下界,即。 相似文献
79.
We propose a new attack on Feistel ciphers with a non-surjective round function such as the CAST cipher family and LOKI91. We extend the attack towards block ciphers that use a non-uniformly distributed round function and apply the extended attack to the CAST family. This attack demonstrates that the round function of a Feistel cipher with six to eight rounds needs to be surjective and sufficiently uniform. 相似文献
80.
Inspired by the promising potential of re-configurable intelligent surface (RIS)-aided transmission in achieving the vision of 6th Generation (6G) network, we analyze the security model for a vehicular-to-infrastructure (V2I) network by considering multiple RISs (M-RIS) on buildings to act as passive relays at fixed distances from a source. In addition, multiple eavesdroppers are presented in the vicinity of the intended destination. Our aim is to enhance the secrecy capacity (SC) and to minimize secrecy outage probability (SOP) in presence of multiple eavesdroppers with the help of M-RIS in V2I communications. We propose a key-less physical layer security using beam-forming by exploiting M-RIS. The proposed approach assumes the concept of detecting eavesdroppers before the information can be transmitted via beam-forming by utilizing M-RIS. The results reveal that with consideration of M-RIS and beam-forming, the achievable SC and SOP performance is significantly improved while imposing minimum power consumption and fewer RIS reflectors. 相似文献