IPS在防御深层攻击中的应用研究

近年来,随着互联网的广泛普及和应用,网络面临的安全问题越来越复杂,对网络造成严重的破坏。本文针对以上问题,首先分析和介绍了网络深层攻击的严重性和入侵防御系统的基本原理与优势。提出了利用IPS技术对网络深层攻击进行防御,实现对来自网络上的各种深层攻击,如对WEB服务器。数据库服务器及各种应用服务器的深层攻击行为进行检测、防御、阻断。     

无线局域网自适应安全管理框架及其应用

针对无线局域网易受攻击、入侵等诸多安全问题,提出一种分布式无线局域网(WLAN)安全管理框架(ASMF),并基于该框架实现了自适应的安全管理系统(ASMS).ASMF框架依据协议分析和测试理论,即:应用主动分析法,通过构造、执行攻击测试用例,与待测协议进行交互,模拟WLAN漏洞的攻击行为,分析WLAN的防御能力;应用被动分析技术,通过实时的网络报文分析、网络性能监测和自适应调整监测策略进行综合的WLAN安全分析和安全管理.与已有的安全系统相比,ASMF不仅能够被动地检测攻击,而且可以主动地探测未知漏洞与威胁,同时根据网络配置自适应调整防御策略,其良好的扩展性使得用户可针对新型攻击的测试、检测和自定制管理策略进行自由扩展.     

大规模网络的主动协同防御模型研究

针对大规模网络所面临的安全问题,提出了一种全方位、立体化纵深的分布式主动协同防御模型,并从模型架构、功能实现机制到模型的算法描述等方面,给出了主动协同防御DDOS攻击和网络蠕虫(或恶意代码)的完整实现方法.该模型通过大规模网络自治域域内和域间之间安全部件的协作,从网络边界层、核心层、子网层到主机层对网络安全问题进行多层次主动协同防御.通过设计一整套主动协同防御的功能实现机制,集成了入侵检测、防火墙和蜜网等安全技术,使该模型不但能够有效地解决大规模网络所面临的安全防御问题,而且还具有良好的通用性和扩展性.     

嵌入式入侵检测及权限管理系统

为了高效、安全地监控网络传输,检测网络中的可疑行为,本系统将入侵检测软件固化在基于SBC84620的嵌入式硬件开发板中,并采用工控领域中广泛使用的实时Linux操作系统,实现了对包括端口扫描、缓冲区溢出攻击、后门攻击、DOS攻击、网络信息收集等的实时检测和防御,降低了开发成本,提高了处理数据的速度。     

安全局域网主机入侵防御系统

安全局域网是一种新型局域网安全方案,其主要特点在于阻止局域网内部泄密行为,增强局域网安全性能。但现有的安全局域网并不具备防御恶意攻击的能力。为加强安全局域网的防攻击能力,该文提出了一种在安全局域网的环境下基于主机的入侵防御系统的设计框架并进行了初步实现。该入侵防御系统能够监视局域网内各个主机的行为,并在事先建立的安全行为规则的基础上,实时判断并阻止局域网中的非法操作,进而防御局域网内的已知和未知入侵行为,保障局域网内的信息安全。     

基于内部网络安全的防火墙系统的改进

针对传统的边界防火墙不能防范来自内部的攻击、效率较低和故障率高、网络应用受到结构性限制等问题,提出了把分布式防火墙系统和分布式入侵检测系统结合在一起的安全防御系统.由防火墙进行访问控制,入侵检测系统检测入侵行为并反馈入侵信息,中央控制平台对各模块统一管理和配置,从而为内部网络提供了立体的、多层次的防御.     

云计算环境中移动网络低匹配度异质信息入侵感知预测算法

针对传统灰色神经网络组合预测算法对网络中入侵信息预测时, 缺乏对低匹配度异质信息的预处理过程, 未对信息入侵攻击意图进行预测, 存在预测准确率低以及入侵防御性能差等问题, 提出一种新的云计算环境中移动网络低匹配度异质信息入侵感知预测算法, 通过灰色模型对初始网络低匹配度异质信息进行预处理. 先采用基于元路径的低匹配度异质信息入侵感知预测算法得到入侵攻击意图矩阵, 再根据该矩阵获取入侵攻击意图函数关系, 实现低匹配度异质信息入侵攻击意图预测. 仿真实验结果表明, 该算法可全面预测信息入侵的意图和过程, 对入侵信息节点防御成功率约为85%, 误警率和漏警率较低, 并具有较高的预测精度.     

云计算环境中移动网络低匹配度异质信息入侵感知预测算法

针对传统灰色神经网络组合预测算法对网络中入侵信息预测时, 缺乏对低匹配度异质信息的预处理过程, 未对信息入侵攻击意图进行预测, 存在预测准确率低以及入侵防御性能差等问题, 提出一种新的云计算环境中移动网络低匹配度异质信息入侵感知预测算法, 通过灰色模型对初始网络低匹配度异质信息进行预处理. 先采用基于元路径的低匹配度异质信息入侵感知预测算法得到入侵攻击意图矩阵, 再根据该矩阵获取入侵攻击意图函数关系, 实现低匹配度异质信息入侵攻击意图预测. 仿真实验结果表明, 该算法可全面预测信息入侵的意图和过程, 对入侵信息节点防御成功率约为85%, 误警率和漏警率较低, 并具有较高的预测精度.     

论网络安全与入侵防御技术

近些年来,随着计算机网络的普及,计算机网络系统被用于提供各种及时、可靠的信息服务。随着网络中攻击行为的愈加普遍,如何降低系统的威胁,保证系统不受侵害等,有关网络安全的话题越来越受社会的关注。文中分析、介绍了当前网络安全现状、网络环境面临的不安全因素,并重点分析了三种网络入侵防御技术——预防入侵、入侵检测、容忍入侵,指出传统防御技术缺乏主动性,网络安全保障体系需要的是一种动态的、主动的防御思想。     

基于蜜罐技术的网络主动防御系统研究

从主动防御的角度研究网络安全策略,介绍了网络安全主动防御系统结构及系统设计中入侵诱骗系统、入侵行为重定向、日志服务器控制等部件的关键实现技术,通过把网络安全主动防御系统与传统的防火墙和入侵检测系统联动,架构基于蜜罐技术的网络安全主动防御系统,将入侵者的入侵行为引入一个可以控制的范围,研究其使用的方法和技术,动态采取相应的防范措施.实验表明,基于蜜罐技术的网络主动防御策略可以有效地抵御来自网络外部的攻击和内部的威胁,实现了网络安全的综合防御,极大地提升了网络安全.     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

An Analysis of Catherine＇s Character——Wuthering Heights

Wuthering Heights, Emily Bronte＇s only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.     

Lower Paleozoic oil relationships within Williston Basin, Canada

The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that     

On the Thermodynamic Limit for Responses to Static Electromagnetic Fields

For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the