Chapter6计算机英语

1、Chapter 6 Network教学目标：教学目标： 掌握计算机网络的概念、协议和种类及要求、拓扑结构的几种类型、各种拓扑结构的优点和缺点等，掌握计算机网络相关的知识。重点：重点：掌握本课中的重点词汇及计算机术语难点：难点：掌握课文中重点句子并能翻译成汉语教学方法：教学方法：讲授法讨论法练习法Chapter 6 Network6.1 Introduction to network一、KeywordsLocal-Area Networks (LAN) 局域网Wide-Area Networks (WAN) 广域网Metropolitan-Area Networks (MAN) 城域网chara

2、cteristic 特征categorize 将 分类topology 拓扑geometric几何的arrangement 布置，方案 bus 总线star 星型ring 环型protocol 协议token-ring network 令牌环网architecture 体系结构node 节点allocate 分配resource 资源Chapter 6 Network6.1 Introduction to network二、Text1.Local-Area Networks (LAN)：The computers are geographically close together (that

3、is, in the same building).2.Wide-Area Networks (WAN): The computers are farther apart and are connected by telephone lines or radio waves.3.Metropolitan-Area Networks (MAN): A data network designed for a town or city.1.Topology: Thee geometric arrangement of a computer system. Common topologies incl

4、ude a bus, star and ring.2.Protocol: The protocol defines a common set of rules and signals that computers on the network use to communicate. One of the most popular protocols for LAN is called Ethernet. Another popular LAN protocol for PCs is the IBM token-ring network.Chapter 6 Network6.2 Protocol

5、一、Keywordsgovern 管理，控制guideline 方针，指导方针regulate 管理，调整CSMA/CD 载波侦听多路访问/冲突检测transmit 传送collision 冲突，碰撞retransmit 再传送delay 延迟wireless access point 无线网关twisted pair 双绞线coaxial cable 同轴电缆fiber op tic cable 光缆concentrator 集线器hub 集线器network interface card 网络接口卡backbone 基干，中枢，主干线copper cable 铜电缆CSMA/CA 载波侦听

6、多路访问/避免冲突serial port 串行口establishment 建立capture 捕获environment 环境FDDI 光纤健分布式数据接口interconnect 互连ATM 异步传输模式ISP 因特网服务提供商Chapter 6 Network6.2 Protocol二、Text A protocol is a set of rules that governs the communications between computers on a network. These rules include guidelines that regulate the follow

7、ing characteristics of a network: access method, allowed physical topologies, types of cabling and speed of data transfer.6.2.1 Fast Ethernet6.2.2 Gigabit Ethernet6.2.3 Local Talk6.2.4 Token Ring 6.2.5 FDDI6.2.6 ATMChapter 6 Network6.3 Topology一、Keywordsterminator 终端shut down 关闭， 关机data flow 数据流disr

8、uption 中断star topology 星型拓扑MAU (multi station access unit) 多站访问部件Tree topology 树型拓扑Chapter 6 Network6.3 Topology二、Text The physical topology of a network refers to the configuration of cables, computers and other peripherals. Physical topology should not be confused with logical topology which is th

9、e method used to pass information between workstations.Chapter 6 Network6.3 Topology二、TextLinear BusAdvantages of a Linear Bus Topology:Easy to connect a computer or peripheral to b linear bus.Requires less cable length than a star topology.Disadvantages of a Linear Bus Topology:Entire network shuts

10、 down if there is a break in the main cable.Terminators are required at both ends of the backbone cable.Difficult to identify the problem if the entire network shuts down.Not meat to be used as a stand-alone solution in a large building.总线型星型Chapter 6 Network6.3 Topology二、TextStarAdvantages of a Sta

11、r Topology:Easy to install and wire.No disruptions to the network when connecting or removing devices.Easy to detect faults and to remove partsDisadvantages of a Star Topology:Requires more cable length than a linear topology.If the hub or concentrator fails, nodes attached are disabled.More expensi

12、ve than linear bus topologies because of the cost of the concentrators.Chapter 6 Network6.3 Topology二、Text树型TreeAdvantages of a Tree Topology:Point-to-point wiring for individual segments.Supported by several hardware and software venders.Disadvantages of a Tree Topology:Overall length of each segme

13、nt is limited by the type of cabling used.If the backbone line breaks, the entire segment goes down.More difficult to configure and wire than other topologies.环型Chapter 6 Network6.3 Topology二、TextStar-Wired Ring A star-wired ring topology may appear（externally）to be the same as a star topology. Inte

14、rnally, the MAU (multi station access unit) of a star-wired ring contains wiring that allows information to pass from one device to another in a circle or ring. The Token Ring protocol uses a star-wired ring topology.Screen English1. Results of virus search.病毒搜索结果。2. Run the current program.运行当前程序。3

15、. Save all modified files.保存所有修改过的文件。4. Scanning memory for Virus. Found virus in memory, Reboot system.检查内存中的病毒。在内存中发现病毒，重新启动系统。5. Screen saver.屏幕保护程序。6. Search all files in file window.搜索文件窗口中的所有文件。7. Search string not found.搜索串未找到。8. Select background color. 选择背景颜色。9. Select another port.选择另一个端口。Screen English10. Send text file.发送文本文件。11. Serial mouse installed.串行鼠标已安装。12. Server application cannot be found.未能找到服务器应用程序。13. Set current command options as the default.将