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Primarily, the thesis assays the condition of network framework, the network was divided into three levels in terms of network management in order to establish the distributed method ,and still pointing out the intention and denotation of studying the Topology Discovery.Next, the thesis analyzes SNMP protocol minutely, including its development, principle, and the Network Management system that established on the SNMP protocol. Have analysed MIB in detail and the application way of MIB in network management .The thesis also assays the ICMP protocol, describing its working principle and the format of datagram minutely , and describing two important tools of ICMP- Ping and TraceRoute in detail. On the base of upper analysis, the thesis expounds a kind of distributed Topology Discovery project, and book it in one autonomy system. Topology Discovery was divided into two levels in terms of network management, and analyses the way of linking up between the two level. The thesis minutely assays Router-Level Topology Discovery technology basing on SNMP and Subnet-Level Topology Discovery technology basing on ARP and ICMP. According to these analyses, the thesis explores the specific methodology and the technology of XML data object which using the WinSNMP API to achieve topology discovering system on the development platform of Visual C++, and also analyses the technology of topology analysis and topology graph minutely. Moreover, the thesis assays the technology of basic firewall and Topology Discovery response strategy. Finally, the thesis analyses the underlying blind problem of the topology finding, and also analyses the reason that the blind problem produced and the way that reduced. The distributed algorithm that this paper puts forward has a certain directive significance in wireless network or other fields.

本文首先分析了网络结构状况，将网络从网络管理的角度划分为三个层次，为分布式的方法奠定了基础，同时还指出拓扑发现研究的目的及意义；接着本文分析了SNMP协议，详细分析了SNMP协议的发展状况，协议的工作原理，以及由SNMP协议基础上建立的SNMP网络管理体系，详细分析了MIB，以及MIB在网络管理上的应用方式；本文又分析了ICMP协议，详细描述了ICMP的工作原理和数据报格式，并详细描述了ICMP的两个重要工具-Ping 和TraceRoute；然后本文在结合上述分析的基础上，提出了一种分布式的拓扑发现方案，将拓扑发现拟订在一个自治系统内，将拓扑发现从网络管理角度划分为路由器级和子网级两个层次，分析了两个层次之间的衔接方式，同时从拓扑地域的角度将拓扑发现过程分布化，分析了分布式算法的具体方法和分布式结点之间的数据通讯方法，本文详细分析了基于SNMP的路由器级拓扑发现技术和基于ARP和ICMP的子网级拓扑发现技术；根据这些分析，本文利用XML数据对象作为分布式算法中的数据对象，分析了XML的技术，本文使用Visual C++开发平台实现网络拓扑发现系统，详细分析了使用WinSNMP API实现基于SNMP的路由器级拓扑发现和基于ARP的子网级拓扑发现，分析了使用Winsock编程实现基于ICMP的子网级拓扑发现，本文还对拓扑分析和拓扑图的绘制技术作了较细致的分析；本文最后还分析了基本防火墙技术，分析了几种类型的防火墙对拓扑发现带来的影响，以及在拓扑发现时的应对策略，本文还分析了拓扑发现中可能产生的盲点问题，分析了盲点产生的原因以及拓扑发现中减少盲点的方法。

It will be taken as undutiful to me if my wife infracts; It will be taken as undutiful to me if my daughter infracts; It will be taken as breaking all bonds of relation if my relatives infracts.

如果妻子不从，视为对夫不忠；如女儿不从，视为对父亲不孝；亲属不从，视为断亲。

We all want an America defined by deep and meaningful equality, from civil rights to labor rights, from women's rights to gay rights...... from ending discrimination to promoting unionization, to providing help for the most important job there is: caring for our families.

我们希望一个由深远而有意义的平等定义的美国，从民权到劳工权利，从妇女权利到同性恋权利，从结束歧视到增进联系进而到帮助完成最重要的工作：关心我们的家庭。

We all want an America defined by deep and meaningful equality, from civil rights to labor rights, from women's rights to gay rights…… from ending discrimination to promoting unionization, to providing help for the most important job there is: caring for our families.

我们都想要这样的美国，被从人权到劳工权利、从女权到同性恋者的权利、从结束歧视到促进团结、到最重要的工作——照顾我们的家人的深刻丰富的平等所定义的美国。

From enterprise annexation and purchase benefit effect angle research merger and acquisition behavior production; From enterprise exterior expansion superiority, economies of scale, transaction cost and management diversification angle, analysis efficiency factor, investment risk factor, market development factor, cost and benefit factor and so on to enterprise annexation and purchase behavior influence; From the complicated and diversified annexation and in the purchase agent, induces has the universal influence agent, and has carried on the concrete analysis to each kind of agent's benefit effect.

从企业兼并与收购旳利益效应角度研究并购行为的产生；从企业外部扩张优势、规模经济、交易费用及经营多样化的角度，分析效率因素、投资风险因素、市场开发因素、成本与效益因素等对企业兼并与收购行为的影响；从复杂多变的兼并与收购的动因中，归纳出具有普遍影响的动因，并对各种动因的利益效应进行le具体的分析。

The theories of physics tell us that any unprompted process of isolated system is always from order to disorder.So only when it is an open system and absorbs negative entropy from the outside,it can be turned from disorder to order.This is the self-organized theory.

物理学理论告诉我们，孤立系统的自发过程总是从有序到无序，只有是开放系统，从外界引入负熵流，才能使系统从无序到有序，这就是自组织理论。

Thus to go from one great novelist to another ── from Jane Austen to Hardy , from Peacock to Trollope , from Scott to Meredith ── is to be wrenched and unrooted; to be thrown this way and then that.

因此，从一个伟大的小说家转向另一个伟大的小说家——从简·奥斯汀到哈代，从皮科克到特罗洛普，从司高特到梅瑞迪斯——会使你困惑不堪，一会儿是这样，一会儿是那样。

He moved on and on quietly, and I, in puzzles, followed him: Time flashed beyond the sink when I was washing hands; it zapped over the bowl when I was having the dinners; and when I was lost in thought it passed across my unwinking eyes.

于是——洗手的时候，日子从水盆里过去；吃饭的时候，日子从饭碗里过去；默默时，便从凝然的双眼前过去。

Starting with the issue of almost used-up IPv4 addresses, this thesis describes the main changes of the IPv6 protocol, analyzes the necessity and urgency of moving from IPv4 to IPv6, studies the pros and cons of major transition techniques from different perspectives, and discusses the transition schemes comprehensively.

本文从当前IPv4地址即将耗尽入手，介绍了IPv6协议的主要变化，分析了从IPv4过渡到IPv6的必要性和紧急性，并且从不同角度出发，研究了各种主流过渡技术的优缺点，对过渡方案进行了的较为全面的探讨。

This paper takes the classifier "Chuan" as a case study to explore the issue of classifier teaching from the angles of Chinese characters, language , cognition and culture, and proposes that TCFL teachers should follow human's cognitive mechanism advancing from easy to difficult and from concrete to abstract to carry out a phased teaching of Chinese classifiers stressing varyingly on their grammar, semantic and pragmatic features by adopting comprehensive teaching methods.

文章以量词"串"为例，从文字、语言、认知和文化等角度对量词教学展开探索，认为教师应遵循人类从易到难，从具象到抽象的认知规律，综合运用多种教学方法对量词的语法、语义和语用开展有所侧重的阶段性教学。

This one mode pays close attention to network credence foundation of the businessman very much.

这一模式非常关注商人的网络信用基础。

Cell morphology of bacterial ghost of Pasteurella multocida was observed by scanning electron microscopy and inactivation ratio was estimated by CFU analysi.

扫描电镜观察多杀性巴氏杆菌细菌幽灵和菌落形成单位评价遗传灭活率。