IPv6下基于协议分析的入侵检测

本文根据下一代因特网IPv6各种协议的结构特点,研究IPv6环境下的协议解码和协议分析的过程,从IPv6网络上收集的数据包,通过协议解码和协议分析,发现不合理代码、恶意代码、不完整的数据包,从而发现入侵行为的特征和规律。     

移动IPv6原理和安全性的研究

IPv6是新一代的 IP协议 ,它对现有协议 IPv4进行改进 ,针对数据包的路由、安全性的改进提出一些新的方案 ,使得移动通信网络接入 ,数据包的路由实现起来更方便。文章介绍了移动 IPv6的协议原理 ,讨论了移动 IPv6的实现策略、机制及特点 ,对 IPv6安全做了分析 ,并对 IPsec安全机制进行了进一步探讨。     

IPComp协议在IPv6中的研究与实现

实际应用中,当对IP数据包应用AH或ESP协议时,会导致传输的IP数据包长度增加,加重网络负载,数据包被再次分段,增大数据传输的时延等问题。介绍了使用IPComp协议对经过IPsec处理的数据包进行压缩的方法,并实现了在支持IPv6协议的Linux平台下数据包经IPComp协议压缩后的数据传输。     

隧道及其应用技术的研究

隧道是一个数据包被封装进另一个数据包的净荷部分进行传送时所经过的路径.介绍了两种典型的隧道协议，讨论了协议中的几个关键技术和隧道的工作原理，论述了它在Virtual Private Network，Virtual Server，IPv4/IPv6过渡策略等领域中的应用.     

互联网通信中信息隐藏技术的应用

分析几种基于TCP和IP协议的信息隐藏方法的原理和优缺点,提出了一种基于TCP/IP协议的隐蔽信道模型。在源主机向目的主机发送秘密数据时,结合隐蔽信道模型,达到安全性和有效性相对较高的目的,并在此基础上设计并实现了一个基于TCP和IP协议字段的秘密数据传输模型。实验表明,该方案正确、有效,对实际工程中的信息隐藏有较高的参考价值。     

隧道及其应用技术的研究

隧道是一个数据包被封装进另一个数据包的净荷部分进行传送时所经过的路径。介绍了两种典型析隧道协议,讨论了协议中的几个关键技术和隧道的工作原理,论述了它在Virtual Private Network,Virtual Server,IPv4/IPv6过渡策略等领域中的应用。     

企业IPv4/IPv6网络ISATAP隧道技术的仿真实现及性能分析

在分析ISATAP隧道技术原理和IPv6地址格式的基础上,基于Dynamips仿真平台部署了一个企业IPv4/IPv6网络,设计了拓扑图和IP地址分配表,解析了主要配置命令,验证了网络的连通性.通过查看路由表信息,明确了ISATAP协议构造IPv6全局单播地址的方法;通过数据包收发率和网络吞吐量,说明网络具有收敛时间快且抖动较为平滑的特性,为ISATAP隧道技术的应用提供了参考依据.     

基于共享网络的数据采集——数据包嗅探器的设计原理

嗅探器是入侵检测系统中信息收集部分的一个很重要的组件．它是一种利用计算机的网络接口截获送往目的地为其他计算机的数据报文的技术，它通过套接字从网络上读取数据包并解析数据包报文头中各字段的意义，从而分析数据帧以及所使用的协议的类型．     

IP压缩在IPSec中的应用

针对IP数据包应用AH或ESP协议的时候，随着数据包长度的增加导致网络负载增加，数据传输时延增加的问题，介绍了使用IPComp对IPSec处理的数据包进行压缩以解决此种问题的方法．在IP报头与载荷之间插入IPComp报头之后，解决了如何修改IPv4和IPv6的域和IPComp关联等关键问题．最后给出了在Linux环境下实现这一方案的方法，验证了此方法的有效性．     

协议一致性测试数据包的构造与解析

数据包的构造与解析是协议一致性测试中的关键技术。在对协议一致性测试原理、特点和流程进行分析的基础上,定义协议一致性测试中的相关概念,建立协议一致性测试中的相关规则,提出一种数据包的构造、发送、捕获和解析的方法,设计数据包构造、发送、捕获和解析算法并对其进行分析。数据包构造算法可依据协议标准规定的消息格式,为每个数据包字段依次赋值;数据包发送算法是通过网络适配器,根据待发送数据包的名称、类型和发送序列,实施数据包的发送;数据包捕获与解析算法是通过网络适配器捕获原始数据包,设置并编译过滤规则,对捕获到的数据包按照协议标准说明进行解析,与预期构造的数据包进行比对。由于设置了过滤规则,有针对性地捕获数据包,因而,提高了数据包的捕获准确率。     

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.     

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.     

Jane Eyre——A Feminist In The 19th Century

In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.     

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     

An affordable accurate evaluation of the binding conformations predicted by molecular docking studies in bio-system

Franck-Condon factors bridge the gap between theoretical modeling and experimental observations for molecular electronic spectroscopy and electron transfer.Under the displaced harmonic oscillator approximation,multidimensional Franck-Condon factors are decomposed into a product of many one-dimensional(1D)Franck-Condon(FC)factors,and each 1D-FC factor is associated with one Huang-Rhys factor that determines the leading contribution of