网络格式

Firstly, the thesis introduced the development of VOD, the background and meaning of the program, then the author introduced the associated technology, mainly including the feature of multimedia, video compression technology and the protocols SCTP and RTP. Considering the ambulant of host , fluctuation of bandwidth,high error rate data in wireless networks ,the author proposed some QoS strategy in the wireless networks such as RTP/SCTP protocol stack , connection control of the server, two buffers in the client end point.,TFC congestion control algorithms ,etc. Based these strategies, the team members gives the software and hardware solution of the wireless video-on-demand system and gives the main modules design of the software system. The system adopted the C/S structure including two parts: server and client ,using the Mpeg-2 which is apporiate for networks as the supported format. The thesis emphatically researches on the video-serving module of the server and the sink module, player module of client.

本文首先介绍了视频点播系统的发展现状、课题的研究背景和意义；接着对课题的相关技术进行概述主要包括了多媒体特点，压缩技术，传输协议SCTP以及RTP；针对无线环境的节点移动性，带宽波动性，数据错误率高等三大特点，作者研究设计了无线环境下的QoS策略：RTP/SCTP协议栈，服务器准入控制机制，客户端双缓冲区，TFRC拥塞控制机制等；在这些策略的基础上设计了系统的软硬件解决方案，并对软件体系结构的主要模块进行了设计，整个视频点播系统采用C/S结构，由服务器，客户端2个部分组成，使用适合网络传输的流媒体格式Mpeg-2作为系统支持的格式，文中重点研究了服务器的视频服务模块以及客户端的接收模块和播放器模块，并利用线程池技术对系统进行实现。

This paper analyzed data from multiple sources and different structures, concluded three types of info: Login info, Event info, and Packet data info, then created the formation for every type of data; In order to combine future possible new data, IDS using profile and formation string together, create and practice data formation standard algorithm; Because in the collected data, there is info that is redundant or has minor effect on the IDS, this paper discussed the rules of redundant data differentiating and safe data differentiating, Then create data filter rule base; Data collecting system uses distributivity design, collecting module like a black box. we can get data which was filterd and had standard formation, if we created a new model string for new data source. Module work individually; filter data right away at the collecting node.

本文分析了多种来源的、不同结构的数据，将其总结成登录信息、事件信息和网络数据包信息三种类型，并为每种类型的数据设计了固定的格式；为了与将来可能出现的新型数据兼容，采用了配置文件与模式字符串相结合的方法，设计并实现了数据格式标准化算法；由于收集到的数据中存在冗余的信息和对入侵检测影响不大的信息，本文分别讨论了冗余数据辨别规则和安全数据辨别规则，并建立起数据过滤规则库；数据收集系统采用分布式设计，收集器以黑盒形式提供，对新的数据源只需设计一个新的模式字符串，即可得到过滤后的、具有标准格式的数据，各收集器间独立工作；在收集点即对数据进行过滤，只向分析中心报告可疑数据，以减少传输和存储的数据量，降低对网络性能的影响。

Aimed at the characteristic of multiple types of faults possibly happened in nuclear power plant, large scale of training sample, and requirement of quick and accurate diagnosing, after the analysis of large sample number generated by large fault type exceeds limitation of 64K paragraph in DOS and large number of local minmum in error surface, measurements of same format of data file, Win95/NT operating system platform, resetting weight learning rate, dynamic training set in quick learning algorithm and improvement on quick learning algorithm using homotopy method which can avoid local minmum points in error surface have been adopted to ensure quickly and effective process of the course of neural network's training and testing.

针对核动力装置可能发生的故障种类多，训练样本规模大，故障诊断需要快速准确的特点等，分析了样本多和故障种类多产生的训练样本量超出DOS段大小和网络误差曲面上局部极小值多的情况，采取了使用相同格式数据文件、Win95/NT操作系统平台，对快速学习算法采用重置神经网络权值学习率和动态训练集、并采用能够有效克服网络误差曲面上局部极小点的同伦方法对学习算法进行改进等措施保证神经网络训练测试过程的快速、有效地进行；针对装置发生的故障须快速、准确诊断的需要，分析了故障的产生对装置参数变化的影响及操纵员对故障诊断的基础，在核动力装置发生故障时参数曲线的变化量与正常运行时参数曲线的变化量存在明显差异的基础上，提出采用参数曲线的变化量作为神经网络的输入，并围绕参数变化量的方法采用二次曲线拟合滤波求变化量和阈值技术来保证神经网络得到精确的装置参数变化量，从而得到准确的诊断结果。

5 WAN Frame Encapsulation Formats frame format:– Flag—Indicates the beginning and end of the frame and is set to the hexadecimal (base 16) pattern 7E.– Address—A 1- or 2-byte field to address the end station in multidrop environments.– Control—Indicates whether the frame is an information, a supervisory, or an unnumbered type frame. It also contains specific function codes.

9.5 广域网帧封装格式帧格式：帧格式：–Flag 标志帧的开始和结尾，设为16进制的7F Flag—标志帧的开始和结尾设为16进制的7 16进制的 Flag 标志帧的开始和结尾，–Address 一个1或2个字节的域，用来在多点的网络 Address—一个个字节的域， Address 一个1 环境中对目标设备寻址–Control 表示帧是一种信息帧，管理帧或者是其他类 Control—表示帧是一种信息帧 Control 表示帧是一种信息帧，型的帧。

Support 720p/1080i - Playback files in PC through wired Ethernet (10/100Mbps)- Playback the recorded contents in HDD; Playback the files stored in HDD - directly playback the files on external devices like USB drive, HDD, Card reader(through USB2.0 Host Port)- support multiple file format: MPEG 1 /2/4, DivX, Xvid, VCD/SVCD/DVD, MP3/WMA, Dolby digital, AC3, JPEG, Kodak picture CD - fast forward/reverse, repeat playback - view Pictures in various ways: Rotate, zoom, music slide show Transferring/storage function - with USB2.0 Target port and USB2.0 Host port - work as USB HDD when connected to USB port on PC for file store / backup / transfer (through USB2.0 Target port)- supports USB drive, HDD, Card reader data exchange (through USB2.0 Host port) Editing recorded A/V title without PC - HDD format - AB Erase, split title, merge title, add chapter mark - Copy, delete, Rename Terminals: Composite video in, composite video out, component video out, left/right audio in, left/right audio out, mini optical audio out, RJ45 net port, USB2.0 Host, USB 2.0 Target HDD Support IDE HDD, support FAT32 File Support FAT32 and NTFS Power: DC12V(1.5A) Power consumption: 1W, 6W.

支持720 p/1080i的影像-播放档案的电脑，通过有线以太网（ 1 0/100）-重放所记录的内容，在硬盘；重放档案储存在硬碟-直接播放该档案的外部设备，如U S B驱动器，硬盘，智能卡阅读器（通过u sb 2 0.0主机端口）-支持多种文件格式：的M PEG1 / 2 / 4 ，转换，音频，视像/格式/数码影碟， m p3/wma，杜比数字， a c3，的J PEG，柯达图片光盘-快速前进/扭转，重复播放-看照片以各种方式：旋转，缩放，音乐幻灯片播放转让/存储功能-与U S B2.0的目标端口和U S B2.0主机端口-工作作为U SB硬碟当连接到US B端口的电脑档案储存/备份/转让（通过USB2.0的目标端口）-支持U SB驱动器，硬盘，智能卡阅读器的数据交换（通过U SB2.0主机端口）编辑记录的音频/视频标题，没有电脑-硬盘格式-抗体抹掉的，分裂的所有权，合并名称，地址章马克-复制，删除，重命名终端：复合视频，复合视频，分量视频输出，左/右音频，左/右音效输出，迷你光学音效输出，接头R J45网络端口， U SB2.0主机， USB 2.0接口目标硬盘支持的IDE硬盘，支持FAT32文件的支持和FAT32和NTFS电源：： DC12V （ 1.5A和）耗电： 789， 6瓦特。

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。

The design includes many new technologies in data exchange and data security, they are: Converting non-XML data to XML in order to apply the XML security technology to more data types; Using the technology of XKMS and PKI to manage the public key in order to overcome the shortage of complexity and difficulty in using PKI and improve the efficiency of the public key management; Using Diffe-Hellman algorithm combining with the public key technology to exchange secret key in order to furthest increase the security of the key; Using the technology of XML digital signature algorithm to ensure the integrity, message authentication and signer authentication of the data; Using the technology of XML encryption to ensure confidentiality of the data; Defining delegable access rules on the structure and content of the XML documents to provide fine-grained access control. According to the XML security framework, a XML security library is designed and implemented.

在对XML及其安全技术主要包括XML加密技术、XML数字签名、公钥管理、密钥产生和交换进行研究的基础上，结合传统密码技术和XML安全技术提出了一种基于XML的数据安全模型，模型中包含了目前网络数据交换和安全领域的一系列最新技术，主要有：将非XML格式数据转换为XML格式数据的方法，以保证现有的大部分网络数据能够应用XML安全技术；使用XML公钥管理技术结合PKI技术管理公钥，以克服PKI技术实施和部署复杂、难度大等问题，提高公钥管理的效率；使用Diffie-Hellman算法结合公钥技术交换密钥，以最大限度保证密钥的安全；使用XML数字签名技术保证数据的完整性、不可否认性和发送方身份认证；使用XML加密技术保证数据的机密性；根据XML文档的内容和结构定义授权访问规则进行良好的访问控制。

So its important for network managers to develop system to monitor network traffic, attacks and resources. It will help network managers to manage network more effectively.The article analyzes two normal approaches to realize network monitor, one is based on packets captured and another is based on logs generated by network gateway. Then, it introduces the three common kinds of log format, syslog, traffic log and WELF.

本文首先分析了网络监视系统实现的常用技术，基于包捕获的技术和基于网关设备日志分析的技术，接着详细分析了三种通用的网络设备日志——Syslog格式日志、Traffic Log格式日志与WELF格式日志，在此基础上详细介绍了本文的重点，基于网关日志分析的网络监视系统一LNMS (Log-based Network Monitor System)的设计和实现。

Whether XML eventually supplants HTML as the standard Web formatting specification depends a lot on whether it is supported by future Web browsers.

XML 能否最终替代 HTML 作为标准的网络格式规范，在很大程度上仰赖于将来的网络浏览器是否支持它。

This research program "network application system of digital map ." serving as a segment of the main program "the digital map making system map maker", which is a research subject of the general section of weapon and equipments, is based on the thoughts of software engineering, and after systematically analyzed and designed by the means of UML( unify to set up the mold language), linked with C++ in general use, are able to directly converts the map data in DXF form into data in unified and open SVG form( the flexible form that can be updated), and realizes to view and interact SVG document accordingly via the JavaScript foot script language on the web page.

本课题作为总装预研项目&全数字地图制图系统Map Maker&的一个组成部分，即数字地图网络应用子系统，它根据软件工程的思想，经UML进行系统分析和设计后，通过C++通用接口，将存储为DXF格式的地图数据文件直接地转换为统一、开放的SVG格式文件(即可升级的矢量图形格式文件)，并且利用JavaScript脚本语言在网页上实现了对SVG文件的浏览和交互操作。

The absorption and distribution of chromium were studied in ryeusing nutrient culture technique and pot experiment.

采用不同浓度K2CrO4(0，0.4，0.8和1.2 mmol/L)的Hoagland营养液处理黑麦幼苗，测定铬在黑麦体内的亚细胞分布、铬化学形态及不同部位的积累。

By analyzing theory foundation of mathematical morphology in the digital image processing, researching morphology arithmetic of the binary Image, discussing two basic forms for the least structure element: dilation and erosion.

通过分析数学形态学在图像中的理论基础，研究二值图像的形态分析算法，探讨最小结构元素的两种基本形态：膨胀和腐蚀；分析了数学形态学复杂算法的基本原理，把数学形态学的部分并行处理理念引入到家实际应用中。