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101.
伴随网络攻击事件的层出不穷,如何有效防范各类网络攻击、加强网络安全保障是网络安全技术的主要内容。本文在分析其攻击原理的基础上,针对这些网络安全隐患讨论和分析了具体的防御策略。 相似文献
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103.
What predicts psychological resilience after disaster? The role of demographics, resources, and life stress. 总被引:1,自引:0,他引:1
Bonanno George A.; Galea Sandro; Bucciarelli Angela; Vlahov David 《Canadian Metallurgical Quarterly》2007,75(5):671
A growing body of evidence suggests that most adults exposed to potentially traumatic events are resilient. However, research on the factors that may promote or deter adult resilience has been limited. This study examined patterns of association between resilience and various sociocontextual factors. The authors used data from a random-digit-dial phone survey (N = 2,752) conducted in the New York City area after the September 11, 2001, terrorist attack. Resilience was defined as having 1 or 0 posttraumatic stress disorder symptoms and as being associated with low levels of depression and substance use. Multivariate analyses indicated that the prevalence of resilience was uniquely predicted by participant gender, age, race/ethnicity, education, level of trauma exposure, income change, social support, frequency of chronic disease, and recent and past life stressors. Implications for future research and intervention are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
104.
Multipath routing in ad hoc networks increases the resiliency against security attacks of collaborating malicious nodes, by maximizing the number of nodes that an adversary must compromise in order to take control of the communication. In this paper, we identify several attacks that render multipath routing protocols vulnerable to collaborating malicious nodes. We propose an on-demand multipath routing protocol, the secure multipath routing protocol (SecMR), and we analyze its security properties. Finally, through simulations, we evaluate the performance of the SecMR protocol in comparison with existing secure multipath routing protocols. 相似文献
105.
汪玉婷 《数字社区&智能家居》2007,(18)
网络上各种协议的制定最初的目的是为了有一个统一的标准可以使通信更方便和在更广泛的范围内实现互通.但就在这些协议成为标准之后,人们在研究它的过程当中发现了协议本身的一些缺陷.同时就有这样的一些恶意和善意的人们利用协议本身的缺陷并结合它们的工作原理研究出了许多对网络进行攻击的方法.本文主要介绍了在网络中存在的一些攻击现象,并分析了各种攻击现象的实现原理. 相似文献
106.
Xiang-Yang Wang Jun Wu 《国际自动化与计算杂志》2007,4(4):428-432
In this paper,a new content-based image watermarking scheme is proposed.The Harris-Laplace detector is adopted to extract feature points,which can survive a variety of attacks.The local characteristic regions (LCRs) are adaptively constructed based on scale-space theory.Then,the LCRs are mapped to geometrically invariant space by using image normalization technique.Finally, several copies of the digital watermark are embedded into the nonoverlapped LCRs by quantizing the magnitude vectors of discrete Fourier transform (DFT) coefficients.By binding a watermark with LCR,resilience against desynchronization attacks can be readily obtained.Simulation results show that the proposed scheme is invisible and robust against various attacks which includes common signals processing and desynchronization attacks. 相似文献
107.
针对污染和重放攻击提出一个新的多源网络编码签名算法,利用同态加密算法构造签名方案来抵御污染攻击,通过引入消息代的序号,防止了代间的重放攻击,并且采用线性计算方法来减少节点的验证时间,降低了对结点计算能力的要求,特别适合于无线传感器网络或自组织网络. 相似文献
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109.
Existing detection methods against SYN flooding attacks are effective only at the later stages when attacking signatures are obvious. In this paper an early stage detecting method (ESDM) is proposed. The ESDM is a simple but effective method to detect SYN flooding attacks at the early stage. In the ESDM the SYN traffic is forecasted by autoregressive integrated moving average model, and non-parametric cumulative sum algorithm is used to find the SYN flooding attacks according to the forecasted traffic. Trace-driven simulations show that ESDM is accurate and efficient to detect the SYN flooding attacks. 相似文献
110.
Software written in one language often needs to construct sentences in another language, such as SQL queries, XML output, or shell command invocations. This is almost always done using unhygienic string manipulation, the concatenation of constants and client-supplied strings. A client can then supply specially crafted input that causes the constructed sentence to be interpreted in an unintended way, leading to an injection attack. We describe a more natural style of programming that yields code that is impervious to injections by construction. Our approach embeds the grammars of the guest languages (e.g. SQL) into that of the host language (e.g. Java) and automatically generates code that maps the embedded language to constructs in the host language that reconstruct the embedded sentences, adding escaping functions where appropriate. This approach is generic, meaning that it can be applied with relative ease to any combination of context-free host and guest languages. 相似文献