Chapter 2 The Internet and World Wide WebE-Commerce Infrastructure（课件）《电子商务专业英语》（中国水利电力出版社）

1 An English Course for E-Commerce (The Second Edition) Chapter 2 The Internet and World Wide Web: E-Commerce Infrastructure Chapter 2 The Internet and World Wide Web: E-Commerce Infrastructure 电子商务专业英语 2-2 Key points: key technology concepts, structural elements and protocols of the Internet Difficult points: how Internet and Web features and services support e-commerce Chapter 2 The Internet and World Wide Web: E-Commerce Infrastructure 2 电子商务专业英语 2-3 Requirements: 了解Internet的起源； 能够确定Internet的关键技术概念； 能够描述 Internet协议与应用程序的作用; 能够解释当前Internet的结构； 理解当前Internet的局限； 能描述Internet II的潜在作用； 理解万维网(World Wide Web)的工作原理； 能够描述Internet和万维网的特征及其服务如何支持电子商务 掌握科技英语词汇的构词法 Chapter 2 The Internet and World Wide Web: E-Commerce Infrastructure 电子商务专业英语 2-4 2.1 The Internet: Technology Background New Words & Expressions: underlying adj.基础的, 根本的 video n.电视, 录象, 视频 bandwidth n. 带宽 hog vt. 贪心攫取；独占 hyperlink n.[计]超链接 pundit n. 空谈家, 权威性的评论者 glibly adv.流利地, 流畅地 conceptualize v.使有概念 legitimization n.合法化, 认为正当 institutional adj.制度上的,机构上的 fledging n.刚会飞的幼鸟,无经验的人 follow-on 继续 slice vt.把...切成薄片; 把...分成部分 break down 破坏；拆散细分；分类 disabled n.禁止使用的 quad n. 四元组 mainframe n.[计]主机, 大型机 Domain Name 域名 vulnerable adj.易受攻击的, 易受...的攻击 reminiscent adj. 怀旧的；回忆的 gigabyte n.十亿字节(giga-为字首,“十亿”) supercomputer n.[计] 超型计算机 host computer (host) 主机 instant messaging 即时信息服务 packet-switching 分组交换技术 client/server 客户机/服务器 Chapter 2 The Internet and World Wide Web: E-Commerce Infrastructure 电子商务专业英语 2-5 2.1 The Internet: Technology Background New Words & Expressions: circuit switching 线路转接 bit n.[计]位, 比特 Router [计] 路由器 routing algorithm 路径算法 Ethernet n.以太网 token ring networks 令牌环形网 Telnet 远程登录 Ping 测试IP地址的程序 Tracert 检查路由器程序 UNIX 美国AT&T公司的操作系统 let alone 更不用说… Finger 查找器(查找因特网用户的程序) Chapter 2 The Internet and World Wide Web: E-Commerce Infrastructure 电子商务专业英语 2-6 What is the Internet? Where did it come from, and how did it support the growth of the World Wide Web? What are the Internet’s most important operating principles? As noted in Chapter 1, the Internet is an interconnected network of thousands of networks and millions of computers (sometimes called host computers or just hosts) linking businesses, educational institutions, government agencies, and individuals together. The Internet provides around 400 million people around the world (and over 170 million people in the United States) with services such as e-mail, newsgroups, shopping, research, instant messaging, music, videos, and news. No one organization controls the Internet or how it functions, nor is it owned by anybody, yet it has provided the infrastructure for a transformation in commerce, scientific research, and culture. The word Internet is derived from the word internetwork or the connecting together of two or more computer networks. The World Wide Web, or Web for short, is one of the Internet’s most popular services, providing access to over one billion Web pages, which are documents created in a programming language called HTML and which can contain text, graphics, audio, video, and other objects, as well as “hyperlinks” that permit a user to jump easily from one page to another. 2.1 The Internet: Technology Background Chapter 2 The Internet and World Wide Web: E-Commerce Infrastructure 电子商务专业英语 2-7 什么是因特网? 它来自何处，和它如何支持万维网的增长? 因特网最重要的运行原则是什么? 如第1章中所指出，因特网是成千上万的网络和数以百万计的计算机(有时被称为主机计算机或主机)将企业、教育机构、政府机关和个人联结起来的一个被互联网络。 因特网为全球大约4亿人(其中美国1.7亿多人)提供诸如电子邮件、新闻讨论组、购物、研究、即时信息、音乐、视频和新闻等服务。 没有任何组织控制英特网或它的运作,它也不被任何人所拥有,尽管它为在商业交易、科学研究和文化提供基础设施。英特网(Internet)这个词起源于internetwork(互连网络)或将两个或更多的计算机网络联接在一起。全球信息网,或简称万维网,是英特网上最流行的服务之一,提供对超过10亿网页的访问，这些网页是由一种叫做HTML(超文本链接标示语言)的编程语言生成的文件，它可以包含本文、图形、声频、视频和其他的对象、以及允许用户容易地跳跃到其他网页的“超链接”。 Chapter 2 The Internet and World Wide Web: E-Commerce Infrastructure 电子商务专业英语 2-8 2.1.1 The Evolution of The Internet 1961–2000 The history of the Internet can be segmented into three phases. In the first phase, the Innovation Phase, from 1961 to 1974, the fundamental building blocks of the Internet were conceptualized and then realized in actual hardware and software. The basic building blocks are: packet-switching hardware, client/server computing, and a communications protocol called TCP/IP (all described more fully below). The original purpose of the Internet, when it was conceived in the late 1960s, was to link together large mainframe computers on college campuses. This kind of one-to-one communication between campuses was previously only possible through the telephone system or postal mail. 因特网的历史可以划分为三个时期。在第一阶段即创新时期，从1961年到1974年，因特网的基本构建模块被概念化并随之用真正的硬件和软件实现。其基本的构建模块是:分组交换硬件、客户/服务器计算技术和一个被称为传输控制协议的通信协议(它们都将在后文全面描述)。当20世纪60年代末期构思的时候，因特网最初的目的是要将大学校园内的大型计算机联结起来。在校园之间这种一对一的通信先前只有经过电话系统或邮政邮件才可能进行。 Chapter 2 The Internet and World Wide Web: E-Commerce Infrastructure 电子商务专业英语 2-9 In the second phase, the Institutional Phase, from 1975 to 1995, large institutions such as the Department of Defense and the National Science Foundation provided funding and legitimization for the fledging invention called the Internet. Once the concept of the Internet had been proven in several government-supported demonstration projects, the Department of Defense contributed a million dollars to develop the concepts and demonstration projects into a robust military communications system that could withstand nuclear war. This effort created what was then called ARPANET (Advanced Research Projects Agency Network). In 1986, the National Science Foundation assumed responsibility for the development of a civilian Internet (then called NSFNet) and began a ten-year-long $200 million expansion program. 在第二阶段，即机构化时期,从1975年到1995年，诸如国防部和国家科学基金委等大机构为这项被称为因特网的刚刚起步的发明提供资金并使其合法化。当因特网的概念在一些政府支持的示范性项目中被证实后，国防部提供了一百万美元资金将这个概念和示范性项目发展成为一个的可以承受核战的军事通信系统。这个努力产生了然后被叫做ARPANET的东西(高级研究计划局建立的计算机网)。在1986年，国家科学基金委承担了建立民用英特网的任务(那时叫做NSFNet)，并且开始了为期十年、投资2亿美元的扩展计划。 Chapter 2 The Internet and World Wide Web: E-Commerce Infrastructure 电子商务专业英语 2-10 In the third phase, the Commercialization Phase, from 1995–2001, government agencies encouraged private corporations to take over and expand both the Internet backbone and local service to ordinary citizens—families and individuals across America and the world who were not students on campuses. By 2000, the Internet’s use had expanded well beyond military installations and research universities. The E-commerce I period begins—arguably—in 1994 with the first effort to advertise and market on the Web. 在第三阶段，即商业化时期,从1995年-2001年，政府机构鼓励私营公司接管并扩展英特网主干和接管为普通市民提供的地方性服务，普通市民包括在全美国和全世界的家庭以及非在校学生的个人。到2000年，英特网的应用已大大超过军事设备和大学研究的范围。电子商务I时期——可以说——是在1994年随着首次尝试网上广告和营销开始的 Chapter 2 The Internet and World Wide Web: E-Commerce Infrastructure 电子商务专业英语 2-11 2.1.2 The Internet: Key Technology Concepts In 1995, the Federal Networking Council (FNC) took the step of passing a resolution formally defining the term Internet. “Internet” refers to the global information system that— is logically linked together by a globally unique address space based on the Internet Protocol (IP) or its subsequent extensions/follow-ons; is able to support communications using the Transmission Control Protocol/Internet Protocol (TCP/IP) suite or its subsequent extensions/follow-ons, and/or other IP-compatible protocols; and provides, uses or makes accessible, either publicly or privately, high level services layered on the communications and related infrastructure described herein. 在 1995 年，联邦网络委员会(FNC)通过了一个关于因特网术语正式定义的决议。 “因特网”是这样的全球信息系统—— 通过以因特网协议或其扩展或继续为基础的、独特的地址空间逻辑性地联结起来； 能够支持使用TCP/IP(传输控制协议/因特网协议)组或其扩展/继续、和/或其他与IP协议(因特网协议)兼容的协议进行的通信；并且 提供、使用或使可访问此处描述的通信和相关基础设施(不论公用的还是专用的)上分层次的高水平服务。 Chapter 2 The Internet and World Wide Web: E-Commerce Infrastructure 电子商务专业英语 2-12 Behind this formal definition are three extremely important concepts that are the basis for understanding the Internet: packet switching, the TCP/IP communications protocol, and client/server computing3. Although the Internet has evolved and changed dramatically in the last 30 years, these three concepts are at the core of how the Internet functions today and are the foundation for Internet II. 在这个正式的定义背后，隐含着三个极端重要的概念: 分组交换、TCP/IP(传输控制协议/网际协议)通信协议和客户机/服务器计算技术，它们乃是理解因特网的基础。尽管因特网在过去30年发生了引人注目的进化和变化，但这三个概念仍是今天因特网运转的核心，也是因特网II基础。 Chapter 2 The Internet and World Wide Web: E-Commerce Infrastructure 电子商务专业英语 2-13 Packet switching is a method of slicing digital messages into parcels called “packets,” sending the packets along different communication paths as they become available, and then reassembling the packets once they arrive at their destination. 分组交换是传输数据的一种方法，它先将数据信息分割成许多称为“分组”的数据信息包；当路径可用时，经过不同的通信路径发送；当到达目的地后，再将它们组装起来。 In packet-switched networks, messages are first broken down into packets. Appended to each packet are digital codes that indicate a source address (the origination point) and a destination address, as well as sequencing information and error control information for the packet. Rather than being sent directly to the destination address, in a packet network, the packets travel from computer to computer until they reach their destination. 在分组交换的网络中，信息首先被分解为许多信息包。每个信息包附加数字代码用于指示其源地址(开始点)和目的地地址、以及顺序信息和错误控制信息。在分组网络中，信息包不是直接被送到目的地地址,而是在计算机到计算机之间旅行直到他们到达目的地。 Chapter 2 The Internet and World Wide Web: E-Commerce Infrastructure 电子商务专业英语 2-14 Packet switching does not require a dedicated circuit but can make use of any spare capacity that is available on any of several hundred circuits. Packet switching makes nearly full use of almost all available communication lines and capacity. Moreover, if some lines are disabled or too busy, the packets can be sent on any available line that eventually leads to the destination point. 分组交换不需要一个专用线路，但是可以利用几百条线路中任何可用的空闲能力。分组交换几乎充分利用了所有可用的通信线路和能力。而且，如果一些线路不通或太忙的话,信息包能在任何可用的、最终通向目的地的线路上传送。 TCP/IP. While packet switching was an enormous advance in communications capacity, there was no universally agreed upon method for breaking up digital messages into packets, routing them to the proper address, and then reassembling them into a coherent message. This was like having a system for producing stamps, but no postal system (a series of post offices and a set of addresses). TCP/IP。尽管分组交换是通信能力的一个巨大进步,但对于将数字信息分解为信息包、将它们传输到适当的地址, 然后重新组装为原来的信息，还没有一种公认的方法。这就像有了一个生产邮票的系统, 但没有邮政系统(一系列的邮局和一套住址)。 Chapter 2 The Internet and World Wide Web: E-Commerce Infrastructure 电子商务专业英语 2-15 TCP/IP answered the problem of what to do with packets on the Internet and how to handle them. TCP refers to the Transmission Control Protocol (TCP). IP refers to the Internet Protocol (IP). A protocol is a set of rules for formatting, ordering, compressing, and error-checking messages. It may also specify the speed of transmission and means by which devices on the network will indicate they have stopped sending and/or receiving messages. Protocols can be implemented in either hardware or software. TCP/IP is implemented in Web software called server software (described below). TCP is the agreed upon protocol for transmitting data packets over the Web. TCP establishes the connections among sending and receiving Web computers, handles the assembly of packets at the point of transmission, and their reassembly at the receiving end. TCP/IP回答了在因特网上用信息包做什么和如何处理信息包的问题。TCP指传输控制协议，IP表示网际协议。协议是一组关于信息的格式化、次序化、压缩和检查错误的规则。它也可以限定传输速度和网上设备指示他们已停止发送及(或)接收信息的方法。协议既可以通过硬件也可通过软件来实现。TCP/IP(传输控制协议/网际协议)通过被称为服务器软件的网络软件来实现(在下文描述)。TCP(传输控制协议)是用来在网上传输数据的公认协议。TCP(传输控制协议)在发送和接收网络计算机之间建立连接,处理信息包在传输点的组装和在接收端的重新组装。 Chapter 2 The Internet and World Wide Web: E-Commerce Infrastructure 电子商务专业英语 2-16 TCP/IP(传输控制协议/网际协议)被分为四个独立的层,由每层处理通信问题的一个不同方面。网络接口层负责信息包在网络媒体上的排列和接收,网络媒体可能是局域网(以太网)、令牌环形网或其他网络技术。TCP/IP(传输控制协议/网际协议)独立于任何地方性网络技术，并能适应在地方性等级上的改变。因特网层负责信息的寻址、封装及其在因特网上的路线排定。通过对信息包去与来应用层的确认和排序，传送层负责为应用层提供通信。应用层为许多应用提供访问较低层服务的能力。一些众所周知的应用是超文本传输协议(HTTP)、文件传输协议(FTP)和简单邮件传输协议(SMTP)。 TCP/IP is divided into four separate layers, with each layer handling a different aspect of the communication problem. The Network Interface Layer is responsible for placing packets on and receiving them from the network medium, which could be a Local Area Network (Ethernet) or Token Ring Network, or other network technology. TCP/IP is independent from any local network technology and can adapt to changes in the local level. The Internet Layer is responsible for addressing, packaging, and routing messages on the Internet. The Transport Layer is responsible for providing communication with the application by acknowledging and sequencing the packets to and from the application. The Application Layer provides a wide variety of applications with the ability to access the services of the lower layers. Some of the best known applications are Hyper Text Transfer Protocol (HTTP), File Transfer Protocol (FTP), and Simple Mail Transfer Protocol (SMTP) . Chapter 2 The Internet and World Wide Web: E-Commerce Infrastructure 电子商务专业英语 2-17 IP Addresses. TCP handles the packetizing and routing of Internet messages. IP provides the Internet’s addressing scheme. Every computer connected to the Internet must be assigned an address—otherwise it cannot send or receive TCP packets. For instance, when you sign onto the Internet using a dial-up telephone modem, your computer is assigned a temporary address by your Internet Service Provider. IP地址。TCP(传输控制协议)处理因特网信息的 分组化和传输路线排定。IP(网际协议)提供因特网的地址分配方案。 每部连接到因特网的计算机必须分配一个地址，否则它不能够发送或接受TCP(传输控制协议)信息包。举例来说，当你在使用调制解调器拨号上网时，你的计算机由因特网服务提供商分配一个临时地址。 Chapter 2 The Internet and World Wide Web: E-Commerce Infrastructure 电子商务专业英语 2-18 Internet addresses, known as IP addresses, are 32-bit numbers that appear as a series of four separate numbers marked off by periods, such as 201.61.186.227. Each of the four numbers can range from 0–255. This “dotted quad” addressing scheme contains up to 4 billion addresses (232). The leftmost number typically indicates the network address of the computer, while remaining numbers help to identify the specific computer within the group that is sending (or receiving ) a message. 因特网地址,即众所周知的IP地址一个32位的数字，它以一串由园点隔开的四个数字出现,例如 201.61.186.227。四个数字中的每一个都在0-255范围内。这个“点分四元组”地址分配方案包含多达到40亿个地址(232)。最左边的那个数字指示计算机的网络地址，而其余的数字帮助识别正在发送(或接收)信息的团体里面一台特定的计算机。 Chapter 2 The Internet and World Wide Web: E-Commerce Infrastructure 电子商务专业英语 2-19 The current version of IP is called Version 4, or IPv4. Because many large corporate and government domains have been given millions of IP addresses each (to accommodate their current and future work forces), and with all the new networks and new Internet-enabled devices requiring unique IP addresses being attached to the Internet, a new version of the IP protocol, called IPv6 is being adopted. This scheme contains 128-bit addresses, or about one quadrillion (1015). IP现在版本叫做4版，或IPv4。因为许多大公司和政府在各自领域已给定数百万个IP地址(适应他们当前和未来的工作量)，而且由于新网络和新的可上网设备需要独特的IP地址，正在采用新版本IP协议IPv6。这个方案包含128位的地址,或曰大约10的15次方个地址。 Chapter 2 The Internet and World Wide Web: E-Commerce Infrastructure 电子商务专业英语 2-20 Domain Names and URLs. Most people cannot remember 32-bit numbers. IP addresses can be represented by a natural language convention called domain names. The domain name system (DNS) allows expressions such as cnet.com to stand for numeric IP addresses (cnet.com’s numeric IP is 216.200.247.134). Uniform resource locators (URLs), which are the addresses used by Web browsers to identify the location of content on the Web, also use domain names as part of the URL. A typical URL contains the protocol to be used when accessing the address, followed by its location. 域名和统一资源定位(URL)。大多数人记不住32位的数字。IP地址可由一个自然语言约定(称为域名)来表示。域名系统(DNS)允许像cnet.com这样的表达代表数值型IP地址(cnet.com 的数值型IP地址是216.200.247.134)。统一的资源定位是网络浏览器用于识别网上内容位置的地址，也使用域名作为它的一部分。一个典型的网址包含访问地址时使用的协议，接着是它的位置。 Chapter 2 The Internet and World Wide Web: E-Commerce Infrastructure 电子商务专业英语 2-21 Client/server computing is a model of computing in which very powerful personal computers called clients are connected together in a network together with one or more server computers. These clients are sufficiently powerful to accomplish complex tasks such as displaying rich graphics, storing large files, and processing graphics and sound files, all on a local desktop or handheld device. Servers are networked computers dedicated to common functions that the client machines on the network need, such as storing files, software applications, utility programs such as Web connections, and printers 客户机/服务器计算技术是一种计算模型，其中相当多台称为客户机的个人计算机联结在一起并与一台或更多的服务器计算机联结在一个网络中。这些客户机功能足够强大以完成复杂的任务如显示丰富的图形、储存大型文件、并处理图形和声音文件，这些任务全部在当地的台式或手持式装置上完成。服务器是联网的计算机，专门用于提供客户机在网上需要的公共功能,例如储存文件、软件应用、公用程序例如网络连接、和打印 Chapter 2 The Internet and World Wide Web: E-Commerce Infrastructure 电子商务专业英语 2-22 2.1.3 Other Internet Protocols and Utility Programs HTTP: Hypertext Documents. HTTP (short for Hyper Text Transfer Protocol) is the Internet protocol used for transferring Web pages (described in the following section). The HTTP protocol runs in the Application Layer of the TCP/IP model. An HTTP session begins when a client’s browser requests a Web page from a remote Internet server. When the server responds by sending the page requested, the HTTP session for that object ends. Because Web pages may have many objects on them—graphics, sound or video files, frames, and so forth—each object must be requested by a separate HTTP message. HTTP: 超文本文档。HTTP(超文本传输转移协议的缩写)是用于传输网页的因特网协议。(下文描述) HTTP协议在TCP/IP模型中的应用层上运行。当一个客户机的浏览器向远程因特网服务器的一个网页发出请求时，HTTP会话开始。当服务器通过发送所请求的页面回应时，关于这个对象的HTTP会话结束。 因为网页可能带有许多对象——图形、声音或视频文件、帧等——每个对象必须由一个独立的HTTP 信息所请求。 Chapter 2 The Internet and World Wide Web: E-Commerce Infrastructure 电子商务专业英语 2-23 SMTP, POP, and IMAP: Sending E-mail. E-mail is one of the oldest, most important, and frequently used Internet services. STMP (Simple Mail Transfer Protocol) is the Internet protocol used to send mail to a server. POP (Post Office Protocol) is used by the client to retrieve mail from an Internet server. You can see how your browser handles SMTP and POP by looking in your browser’s Preferences or Tools section, where the mail settings are defined. You can set POP to retrieve e-mail messages from the server and then delete the messages on the server, or retain them on the server. IMAP (Internet Message Access Protocol) is a more current e-mail protocol supported by many servers and all browsers. IMAP allows users to search, organize, and filter their mail prior to downloading it from the server. SMTP、POP和IMAP:发送电子邮件。电子邮件是最老、最重要和经常使用的因特网服务之一。STMP(简单邮件传输协议)是用于将将邮件发送到服务器的因特网协议。客户机利用POP(邮局协议)从因特网服务器的检索邮件。你可以通过察看浏览器上“收藏”和“工具”栏看见你的浏览器如何处理 SMTP和POP协议,邮件设定在这两栏定义。你可以设定用POP协议取回来自服务器的电子邮件信息然后删除服务器上的信息, 或在服务器上保留他们。 IMAP(因特网消息访问协议)是一个由许多服务器和所有的浏览器支持的更通用的电子邮件协议。 IMAP允许使用者在从服务器下载邮件之前搜寻、组织和过滤邮件。 Chapter 2 The Internet and World Wide Web: E-Commerce Infrastructure 电子商务专业英语 2-24 FTP: Transferring Files. FTP (File Transfer Protocol) is one of the original Internet services. It is a part of the TCP/IP protocol and permits users to transfer files from the server to their client machine, and vice versa. The files can be documents, programs, or large database files. FTP is the fastest and most convenient way to transfer files larger than 1 megabyte, which many mail servers will not accept. SSL: Security. SSL (Secure Sockets Layer) is a protocol that operates between the Transport and Application Layers of TCP/IP and secures communications between the client and the server. SSL helps secure e-commerce communications and payments through a variety of techniques such as message encryption and digital signatures. FTP:传输文件。FTP(文件传输协议)是最初的因特网服务之一。它是TCP/IP协议的一部份，它允许用户把文件从服务器传送到客户机，反之亦然。文件可以是文档、程序、或大型数据库文件。FTP是传输大于1M文件最快速和最方便的方法，而许多邮件服务器将不接受大于1M的文件。 SSL:安全性。SSL(加密套接字协议层)是一个在TCP/IP中运行于的传输层和应用层之间的、确保客户机与服务器之间通信安全的协议。通过诸如信息加密和数字签名等多种技术，SSL促进安全的电子商务通信和支付。 Chapter 2 The Internet and World Wide Web: E-Commerce Infrastructure 电子商务专业英语 2-25 Telnet: Running Remote. Telnet is a terminal emulation program that runs in TCP/IP. You can run Telnet from your client machine. When you do so, your client emulates a mainframe computer terminal. (The industry standard terminals defined in the days of mainframe computing are VT-52, VT-100, and IBM 3250.) You can then attach yourself to a computer on the Internet that supports Telnet and run programs or download files from that computer. Telnet was the first “remote work” program that permitted users to work on a computer from a remote location. Telnet(远程登录):远程运行。Telnet是一个在TCP/IP中运行的终端模拟程序。你能从你的客户机运行Telnet。当你这么做的时候,你的客户机模拟一个主机计算机终端。(定义于大型机计算时代的工业标准终端是VT-52、VT-100和IBM 3250)。然后你能接入到一台因特网上支持Telnet的计算机上，从那部计算机运行程序或下载文件。Telnet是允许用户在远方的一部计算机上工作的第一个“远程工作”程序。 Chapter 2 The Internet and World Wide Web: E-Commerce Infrastructure 电子商务专业英语 2-26 Finger: Finding People. You can find out who is logged onto a remote network by using Telnet to connect to a server, and then typing “finger” at the prompt. Finger is a utility program supported by UNIX computers. Ping: Testing the Address. You can “ping” a host computer to check the connection between your client and the server. The ping (Packet InterNet Groper) program will also tell you the time it takes for the server to respond, giving you some idea about the speed of the server and the Internet at that moment. Tracert: Checking Routes. Tracert is one of a several route-tracing utilities that allow you to follow the path of a message you send from your client to a remote computer on the Internet. Finger: 发现人们。通过使用Telnet连接到一个服务器上,然后在提示符的键入"Finger",你能发现谁登录到远程网络。Finger是一个UNIX 计算机支持的公用程。 Ping:检测地址。你可以“Ping”一台主机计算机来检查你的客户机和服务器之间的连结。给出你有关服务器和因特网速度的一些建议，Ping(信息包因特网Groper)程序还将会告诉你服务器回应所需的时间。 Tracert：检查路径。Tracert是几种追踪路径的公用程序之一,它允许你跟踪你在因特网上从客户机向远程计算机发出的信息的路径。 Chapter 2 The Internet and World Wide Web: E-Commerce Infrastructure 电子商务专业英语 2-27 2.2 The Internet Today New Words & Phrases substrate n. 衬底，基底 middleware n.中间设备,中间件 authentication n.证明, 鉴定 repository n. 储存库，资料档案库 backbone n.主干,干线 pipeline n. 流水线，管线 Mbps n. 兆比特每秒 Gbps n. 千兆比特每秒 redundancy n.冗余 built-in adj.内置的, 嵌入的n.内置 tier n.一层，一排 curb n.路边 mom and pop shop n.小零售铺 dial-up 拨号上网 narrowband n. 窄带 broadband n. 宽带 throughput n. 吞吐量, 生产能力 objectionable adj. 反对的,不能采用的 modem n.调制解调器 delay n.延迟 aficionado n.<西班牙>狂热爱好者, 迷 sovereign adj.统治的; n.统治者 Intranet 企业内部互联网 Extranets 企业外部互联网 piggyback n.机载 ; v.搭载 Chapter 2 The Internet and World Wide Web: E-Commerce Infrastructure 电子商务专业英语 2-28 2.2 The Internet Today The Internet can be viewed conceptually as having four layers: the network technology substrate, transport services and representation standards, middleware services, and applications. The network technology substrate is composed of telecommunications networks and protocols. The transport layer houses the TCP/IP protocol. The applications layer contains client applications such as the World Wide Web, e-mail, and audio or video playback. Middleware is the glue that ties the applications to the communications networks, and includes such services as security, authentication, addresses, and storage repositories. Users work with applications (such as e-mail) and rarely become aware of middleware that operates in the background. Because all layers use TCP/IP and other common standards linking all four layers, it is possible for there to be significant changes in the network layer without forcing changes in the applications layer. 因特网能被概念性地分为四层：网络技术基体、传送服务和表示标准、中间件服务和应用。网络技术基体由电信网络和协议组成。传送层收容TCP/IP协议。应用层包含客户机的应用，例如万维网、电子邮件和声频或视频回放。中间件是将应用与通信网络连接起来的粘合剂, 并且包括如安全、验证、地址和存储等服务。用户通过应用(例如电子邮件)工作，很少知道中间件在后台运行。因为各层使用TCP/IP协议和其他公共标准联结所有四层,所以在网络层发生重大变化而不强迫应用层变化是可能的。 Chapter 2 The Internet and World Wide Web: E-Commerce Infrastructure 电子商务专业英语 2-29 2.2.1 The Internet Backbone The Internet’s backbone is formed by Network Service Providers (NSPs), which own and control the major networks. The backbone has been likened to a giant pipeline that transports data around the world in milliseconds. In the United States, the backbone is composed entirely of fiber-optic cable (described more fully below), with bandwidths ranging from 155 Mbps to 2.5 Gbps. Bandwidth measures how much data can be transferred over a communications medium within a fixed period of time, and is usually expressed in bits per second (bps), kilobits (thousands of bits) per second (Kbps), megabits (millions of bits) per second (Mbps), or gigabits (billions of bits) per second (Gbps). 因特网主干由拥有且控制主要的网络的网络服务提供商(NSPs)形成。主干被比作一个能在几毫秒中将数据传遍全球的巨大通道。在美国，主干完全由光缆(在文下更完整地描述)组成，其带宽从155兆比特/秒到2.5吉比特/秒。带宽衡量在固定的时间内、通过某种通信媒体能传输多少数据，通常以每秒位(bps)、每秒千位 (Kbps)、每秒兆位(Mbps)或千兆位(Gbps)来表示。 Chapter 2 The Internet and World Wide Web: E-Commerce Infrastructure 电子商务专业英语 2-30 Connections to other continents are made via a combination of undersea fiber optic cable and satellite links. The backbones in foreign countries typically are operated by a mixture of private and public owners. The U.S. backbone is one of the most developed because the Internet’s infrastructure was developed here. The backbone has built-in redundancy so that if one part breaks down, data can be rerouted to another part of the backbone. Redundancy refers to multiple duplicate devices and paths in a network. 与其他大陆的连接是经由海底光缆和人造卫星联通的。在外国，因特网主干是由私营和国有公司共同经营的。美国的因特网主干是(全世界)最发达的(主干)之一，因为因特网的基础是从这里发展起来的。因特网主干具有内在的冗余，以便如果主干的一部分崩溃,数据可以改行其他部份。冗余指在网络中设备和路径的多重副本。 Chapter 2 The Internet and World Wide Web: E-Commerce Infrastructure 电子商务专业英语 2-31 2.2.2 Network access points and metropolitan area exchanges In the United States there are a number of hubs where the backbone intersects with regional and local networks, and where the backbone owners connect with one another1. These hubs are called Network Access Points (NAPs) or Metropolitan Area Exchanges (MAEs), and use high-speed switching computers to connect the backbone to regional and local networks, and exchange messages with one another. The regional and local networks are owned by local Bell operating companies (RBOCs—pronounced “ree-bocks”), and private telecommunications firms such as MFS Corporation; they generally are fiber optic networks operating at over 100 Mbps. The regional networks lease access to Internet Service Providers, private companies, and government institutions. 在美国，有许多网络中心——此处因特网主干与区域性和地方性网络交叉，主干拥有者也在此处彼此连接。这些网络中心被称为网络访问节点(NAPs)或城域交换站(MAEs),而且它们使用高速交换计算机联结主干与地方性和区域性网络、并彼此交换信息。区域性和地方性网络由地方贝尔运营公司(RBOCs-发音 "ree-bocks")和私营电信公司例如MFS公司所拥有；它们通常是以超过100Mbps带宽运行的光纤网络。区域性网络从因特网服务提供商、私营公司和政府机构租用使用权。 Chapter 2 The Internet and World Wide Web: E-Commerce Infrastructure 电子商务专业英语 2-32 2.2.3 Campus Networks There are an estimated one million campus networks attached to the Internet worldwide (Computer Industry Almanac Inc., 2001). Campus networks are generally local area networks operating with a single organization— such as New York University or Microsoft Corporation. In fact, most large organizations have hundreds of such local area networks. These organizations (representing about 60 million workers) are sufficiently large that they lease access to the Web directly from regional and national carriers. These local area networks generally are running Ethernet (a local area network protocol) and have operating systems such as Windows 2000 (NT), Novell, or others that permit desktop clients to connect to the Internet through a local Internet server attached to their campus networks. Connection speeds in campus networks are in the range of 10–100 Mbps to the desktop. 估计全世界有100万个校园网联结到因特网(计算机工业年间鉴公司,2001年)。校园网通常是一个组织运营的局域网，例如纽约大学或微软公司。事实上，大部分大组织有几百个这样的局域网。这些组织(代表大约6亿工人)足够大，以至于他们直接向区域性和国家通信公司租用对网络的访问。这些局域网通常是运行的以太网(一种局域网协议)，并且具有例如Windows2000(NT)、Novell或其他操作系统，允许桌面客户机通过一个连接到校园网的因特网服务器联到因特网。在校园网中，台式机的连接速度在10-100 Mbps。 Chapter 2 The Internet and World Wide Web: E-Commerce Infrastructure 电子商务专业英语 2-33 2.2.4 Internet Service Providers The firms that provide the lowest level of service in the multi-tiered Internet architecture by leasing Internet access to home owners, small businesses, and some large institutions are called Internet Service Providers (ISPs)2. ISPs are retail providers—they deal with “the last mile of service” to the curb, the home, the business office. About 45 million American households connect to the Internet through either national or local ISPs. ISPs typically connect to the Internet and MAEs or NAPs with high-speed telephone or cable lines (up to 45 Mbps). 在多层次因特网体系中通过向家庭出租因特网访问通道提供最低水平服务的公司、小型企业，和一些大机构叫做因特网服务提供商(ISP)。因特网服务提供商是零售型供给者——他们为街头、家庭、企业办公室处理“最后一步服务”。约4500万个美国的家庭通过全国性的或地方性的ISP连接到因特网。因特网服务提供商有利用高速电话或电缆线(高达45 Mbps)典型地连接到因特网和城域交换站或网络访问节点。 Chapter 2 The Internet and World Wide Web: E-Commerce Infrastructure 电子商务专业英语 2-34 There are two types of ISP service: narrowband and broadband. Narrowband service is the traditional telephone modem connection now operating at 56.6 Kbps (although the actual throughput hovers around 30 Kbps due to line noise that causes extensive resending of packets). This is the most common form of connection worldwide. Broadband service is based on DSL, cable modem, telephone (T1 and T3 lines), and satellite technologies. Broadband—in the context of Internet service —refers to any communication technology that permits clients to play streaming audio and video files at acceptable speeds—generally anything above 100 Kbps. 因特网服务提供商提供两种服务:窄带和宽带。窄带服务是目前以56.6 Kbps运行的传统电话调制解调器连接(虽然由于线路噪音造成大量的信息包重新发送,真正的吞吐量徘徊在30Kbps附近)。这是全世界最普通的联结形式。宽频服务以数字用户专线、电缆调制解调器，电话(T1和T3线)和人造卫星技术为基础。 在因特网服务的环境中，宽频指的是任何允许客户机以可接受的速度运行流型声频和视频文件的通信技术，通常可接受的速度指在100 Kbps以上。 Chapter 2 The Internet and World Wide Web: E-Commerce Infrastructure 电子商务专业英语 2-35 2.2.5 Intranets and Extranets The very same Internet technologies that make it possible to operate a worldwide public network can also be used by private and government organizations as internal networks. An intranet is a TCP/IP network located within a single organization for purposes of communications and information processing. Many corporations are moving away from proprietary local area networks such as Windows 2000 and Novell, and toward a single internal intranet to handle the firm’s information processing and communication needs. Internet technologies are generally far less expensive than proprietary networks, and there is a global source of new applications that can run on intranets. In fact, all the applications available on the public Internet can be used in private intranets. 使全球性公众网络运转成为可能的、与因特网技术相同的技术也能被私营和政府组织用于内部网络。内联网是一个组织内部用于通信和信息处理的TCP/IP网络。许多公司正在远离专有局域网例如Windows 2000和Novell,并转向一个单的企业内联网以处理公司的信息和通信需要。因特网技术通常远比专有网络技术价廉，而且拥有一个全球资源获得可在内联网上运行的新应用。事实上，在公用因特网上得到的所有应用都能在专用内联网使用。 Chapter 2 The Internet and World Wide Web: E-Commerce Infrastructure 电子商务专业英语 2-36 Extranets are formed when firms permit outsiders to access their internal TCP/IP networks. For instance, General Motors permits parts suppliers to gain access to GM’s intranet that contains GM’s production schedules4. In this way, parts suppliers know exactly when GM needs parts, and where and when to deliver the parts. Intranets and extranets generally do not involve commercial transactions in a marketplace, and they are mostly beyond the scope of this text. Extranets will receive some attention as a type of B2B exchange. 当公司允许局外人访问他们的内部TCP/IP网络时，外联网就形成了。举例来说，通用汽车公司允许零部件供应商访问公司的内联网，它的内联网包含生产进度。这样，零部件供应商能完全了解通用汽车公司什么时候需要零部件,和到哪里与何时递送零部件。 在一个市场中，内联网和外联网通常不涉及商业交易, 而且他们大部分超过了本文的范围。作为一种B2B交换市场，外联网将会受到一些关注。 Chapter 2 The Internet and World Wide Web: E-Commerce Infrastructure 电子商务专业英语 2-37 2.2.6 Who Governs The Internet? Aficionados and promoters of the Internet often claim that the Internet is governed by no one, and indeed cannot be governed, and that it is inherently above and beyond the law. In fact, the Internet is tied into a complex web of governing bodies, national legislatures, and international professional societies. There is no one governing body that controls activity on the Internet. Instead, there are several organizations that influence the system and monitor its operations. Among the governing bodies of the Internet are: 因特网的热爱者和促进者时常宣称因特网没有被任何人统治,也的确不能被统治,而且还宣称它天生高于法律。事实上，因特网被连入了由管理机构、国家立法机构和国际专业协会织成的一张复杂的网之中。没有一个管理机构可以控制因特网上的活动，而是有几个组织影响它的系统、且监测它的运行。在因特网管理机构中有: Chapter 2 The Internet and World Wide Web: E-Commerce Infrastructure 电子商务专业英语 2-38 The Internet Architecture Board (IAB), which helps define the overall structure of the Internet. The Internet Corporation for Assigned Names and Numbers (ICANN), which assigns IP addresses, and the Internet Network Information Center (InterNIC), which assigns domain names. The Internet Engineering Steering Group (IESG), which oversees standard setting with respect to the Internet. The Internet Engineering Task Force (IETF), which forecasts the next step in the growth of the Internet, keeping watch over its evolution and operation. The Internet Society (ISOC), which is a consortium of corporations, government agencies, and nonprofit organizations that monitors Internet policies and practices. The World Wide Web Consortium (W3C), which sets HTML and other programming standards for the Web. 因特网架构委员会(IAB)帮助定义因特网的总体结构。 因特网域名与地址管理委员会(ICANN)负责分配IP地址；和因特网网络信息中心(InterNIC)负责分配域名。 因特网工程指导组(IESG)监督有关因特网的标准设定。 因特网工程任务组(IETF)预测因特网成长的下一步,监视它的进化和运行。 因特网协会(ISOC)是一个公司、政府机关以及监测因特网政策与实践的非营利性组织的联盟。 万维网联合会(W3C)为万维网设定HTML和其他编程标准。 Chapter 2 The Internet and World Wide Web: E-Commerce Infrastructure 电子商务专业英语 2-39 While none of these organizations has actual control over the Internet and how it functions, they can and do influence government agencies, major network owners, ISPs, corporations, and software developers with the goal of keeping the Internet operating as efficiently as possible. 尽管这些组织中没有一个能真正控制因特网及其如何运行,他们可以就保持因特网尽可能高效运行的目标影响政府机关、主要网络拥有者、公司、因特网服务提供商和软件开发者。 In addition to these professional bodies, the Internet must also conform to the laws of the sovereign nation-states in which it operates, as well as the technical infrastructures that exist within the nation-state. Although in the early years of the Internet and the Web there was very little legislative or executive interference, this situation will change in the near future as the Internet plays a growing role in the distribution of information and knowledge, including content that some find objectionable. 除了这些专业团体，因特网还必须符合所在的主权民族国家的法律,和这个民族国家存在的技术基础。虽然因特网和万维网在早年很少受到司法与或行政干涉,这种情形在不久的将来就会改变，因为因特网在传播信息和知识方面扮演越来越重要的角色,包括一些有人反对的内容。 Chapter 2 The Internet and World Wide Web: E-Commerce Infrastructure 电子商务专业英语 2-40 2.3 Internet II: The Future Infrastructure New Words & Phrases congestion n.阻塞 appreciate vt. 领会，鉴赏, 感激circuitous adj.迂回线路的 latency n.等待时间 streaming adj.流型的; n.流 synchronous adj.同时的, 同步的 jerkiness n.不平稳,颠簸 tag n. 标志，特征，标记[识]；标识符 multicasting 多信道广播(技术，方法) multicasting n. 多信道广播(技术，方法) diffserve 区别质量的服务 videoconference n.视频会 Chapter 2 The Internet and World Wide Web: E-Commerce Infrastructure 电子商务专业英语 2-41 2.3 Internet II: The Future Infrastructure 2.3.1 Limitations of Internet I Much of the Internet’s current infrastructure is several decades old (equivalent to a century in Internet time). It suffers from a number of limitations, including: Bandwidth limitations. There is insufficient capacity throughout the backbone, the metropolitan switching centers, and most importantly, to the “last mile” to the house and small business. The result is slow service (congestion) and a very limited ability to handle video and voice traffic. Quality of service limitations. Today’s information packets take a circuitous route to get to their final destinations. This creates the phenomenon of latency— delays in messages caused by the uneven flow of information packets through the network. Network architecture limitations. Today, a thousand requests for a single music track from a central server will result in a thousand efforts by the server to download the music to each requesting client. This slows down network performance as the same music track is sent out a thousand times to clients that might be located in the same metropolitan area. This is very different from television, where the program is broadcast once to millions of homes. Language development limitations. HTML, the language of Web pages, is fine for text and simple graphics, but poor at defining and communicating “rich documents” such as databases, business documents, or graphics. Chapter 2 The Internet and World Wide Web: E-Commerce Infrastructure 电子商务专业英语 2-42 2.3.1 因特网I的限制 许多因特网现在的基础设施是几十年以前的(在因特网时代等于一个世纪)。它承受许多限制,包括: 带宽限制。在主干、城市交换中心和最重要的最终对家庭和小型企业都存在着容量不足的问题。其结果是极慢的服务(阻塞)和相当有限的处理音频、视频的能力。 服务品质限制。今天的信息包需经过迂回路径到达目的地。这就产生了等待时间的现象——由于信息包通过网络时流动不畅通引起的信息延迟。 网络结构限制。今天，对来自一个中央服务器的一个音乐辑发出一千个请求，将会造成服务器为每个请求的客户机下载音乐而动作一千次。当同一个音乐辑被送出一千次到可能位于相同城区的客户机，就减慢了网络性能。这非常不同于电视,电视节目一次对数以百万计的家庭广播。 语言发展限制。HTML网页语言,对本文和简单的图形是好的,但在定义和传递如数据库、商业文件或图形等"富文件"时是不够的。 Chapter 2 The Internet and World Wide Web: E-Commerce Infrastructure 电子商务专业英语 2-43 2.3.2 The Internet2® Project Internet2® is a consortium of more than 180 universities, government agencies, and private businesses that are collaborating to find ways to make the Internet more efficient. Their work together is a continuation of the kind of cooperation among government, private, and educational organizations that created the original Internet. The idea behind Internet2 is to create a “giant test bed” where new technologies can be tested without impacting the existing Internet. 2.3.2 INTERNET2工程 Internet2®是超过180所大学、政府机关和私营企业通力合作寻找使因特网更高效方法的一个联盟。 他们的协同工作是最初产生因特网时政府、私营与教育机构合作的继续。 Internet2的设想是产生一个"巨大的试验基地"，可以在对现有因特网不造成冲击的情况下对新技术进行试验。 Chapter 2 The Internet and World Wide Web: E-Commerce Infrastructure 电子商务专业英语 2-44 Internet2 的三个主要目标是: 为全国研究界产生一个前沿网络能力; 使因特网革命性的应用能够实现；和 确保使新网络服务和应用迅速传递到更广泛的因特网社区。 The three primary goals of Internet2 are to: Create a leading edge network capability for the national research community; Enable revolutionary Internet applications; and Ensure the rapid transfer of new network services and applications to the broader Internet community. Chapter 2 The Internet and World Wide Web: E-Commerce Infrastructure 电子商务专业英语 2-45 2.3.3 The Larger Internet II Technology Environment The Internet2 project is just the tip of the iceberg when it comes to near-term future enhancements to the Internet. In fact, we believe that a whole new era is about to begin that we call Internet II. For instance, NGI (Next Generation Internet) is another project initiated and sponsored by the federal government that is focused on developing advanced applications and networking capabilities needed by U.S. government agencies such as NASA and the Department of Energy. In addition, other groups—mostly private corporations and industries—are making extraordinary efforts to expand Internet capacity in order to support new services and products that they believe the public will demand in the near future. 当提起因特网近期未来的提高时，Internet2工程仅仅是冰山一角。事实上，我们相信一个全新的时代即将开始，我们称之为因特网II。例如，NGI(下一代因特网)是联邦政府发起并赞助的另一项工程，重点是发展先进的应用和诸如国家航空航天局和能源部等美国政府机关需要的网络能力。此外,其他团体——大部分是私营公司和企业——正在尽力扩展因特网容量以支持他们相信在不久的将来公众就会需要的新服务和产品。 Chapter 2 The Internet and World Wide Web: E-Commerce Infrastructure 电子商务专业英语 2-46 The increased bandwidth and expanded network connections of the Internet II era will result in benefits beyond faster access and richer communications. Enhanced reliability and quality of Internet transmissions will create new business models and opportunities. Some of the major benefits of these technological advancements include IP multicasting, latency solutions, guaranteed service levels, lower error rates, and declining costs. 因特网II时代增加的带宽与扩大的网络连接造就的利益不只是更快的访问和更丰富的通信。因特网传输的可靠性与质量的提高将会造就新的商业模型和机会。这些技术进步的一些主要的益处包括IP多信道广播、 等待时间解决方案、有保证的服务水平、低错误率和成本的降低。 Chapter 2 The Internet and World Wide Web: E-Commerce Infrastructure 电子商务专业英语 2-47 IP Multicasting. IP multicasting is a set of technologies that enables efficient delivery of data to many locations on a network. Rather than making multiple copies of a message intended to be distributed to multiple recipients at the point of origin of a message, multicasting initially sends just one message and does not copy it to the individual recipients until it reaches the closest common point on the network, thereby minimizing the bandwidth consumed. Network performance is significantly improved because it isn’t bogged down with the processing and transmission of several large data files; each receiving computer doesn’t have to query the transmitting server for the file. Multicasting technologies are already making their way into today’s Internet through the use of Mbone (a special-purpose backbone for delivering video data). IP多信道广播。IP多信道广播是使一组数据向网络中许多位置高效递送的技术。不是将一个信息在源点复制多份向多个接收者分配,多信道广播开始时只是发出一份信息而不向接收者复制，直到它到达网络上最近的公共点，因此使消耗的带宽最少。因为它不会因处理和传输一些大的数据文件陷入停顿，所以网络型能大大地被改良；每个接收计算机不必为一个文件向传输服务器发出请求。多信道广播技术已经通过Mbone(用于递送视频数据的一种专用主干)的使用在今天的因特网上获得进展。 Chapter 2 The Internet and World Wide Web: E-Commerce Infrastructure 电子商务专业英语 2-48 Latency Solutions. One of the challenges of packet switching, where data is divided into chunks and then sent separately to meet again at the destination, is that the Internet does not differentiate between high-priority packets, such as video clips, and those of lower priority, such as self-contained e-mail messages. Because the packets cannot yet be simultaneously reassembled, the result is distorted audio and video streams. Internet II, however, holds the promise of diffserve, or differentiated quality of service—a new technology that assigns levels of priority to packets based on the type of data being transmitted. Videoconference packets, for example, which need to reach their destination almost instantaneously, would receive much higher priority than e-mail messages. In the end, the quality of video and audio will skyrocket without undue stress on the network. Live and on-demand TV and video will be possible once Internet II is completed. 等待时间解决方案。将数据分为多块、然后分开传送以便到目的地后再集合的分组交换技术，面临的挑战之一是因特网不区别高优先权信息包如图像修剪,与低优先权信息包如自我包容的电子邮件信息。因为信息包不能然同时重新装配,结果导致声频与视频流失真。 然而因特网II承诺区别服务品质——一种以被传输的数据类型为基础为信息包分配优先权等级的新技术。例如，视讯会议信息包需要几乎即时到达目的地,将接受比电子邮件信息高的多的优先权。最后，由于在网上没有了过度的压力，视频和声频的质量将猛涨。一旦因特网II完成，实况和随选电视与视频将成为可能。 Chapter 2 The Internet and World Wide Web: E-Commerce Infrastructure 电子商务专业英语 2-49 Guaranteed Service Levels. In today’s Internet, there is no service-level guarantee and no way to purchase the right to move data through the Internet at a fixed pace. The Internet is democratic—it speeds or slows everyone’s traffic alike. With Internet II, it will be possible to purchase the right to move data through the network at a guaranteed speed in return for higher fees. Lower Error Rates. Improved capacity and packet switching will inevitably impact quality of data transmissions, reducing error rates and boosting customer satisfaction. 有保证的服务水平。在今天的因特网中, 没有任何服务水平保证也没有办法购买以固定速度通过因特网移动数据。因特网是民主的——它加速度或减慢每个人通信量。通过因特网II，将可购买以有保障的速度经过网络移动数据的权利，作为对较高费用的回报。 更低的错误率。改进的能力和分组交换不可避免地意影响数据传输的质量，减少错误率而提高客户满意度。 Chapter 2 The Internet and World Wide Web: E-Commerce Infrastructure 电子商务专业英语 2-50 Declining Costs. As the Internet pipeline is upgraded, the availability of broadband service will expand beyond major metropolitan areas, significantly reducing the costs of access. More users means lower cost, as products and technology catch on in the mass market. Higher volume usage enables providers to lower the cost of both access devices, or clients, and the service required to use such products. Both broadband and wireless service fees are expected to decline as geographic service areas increase, in part due to competition for that business. 费用的降低。由于因特网通道升级,宽频服务的有效性将会超过主要大城市的范围，大大地降低访问的费用。较多的使用者意味比较低的费用,如同产品和技术在大众的市场中流行一样。较多的使用准许供应商降低访问设备或客户机的费用和服务必需使用的此类产品费用。随着服务的地理区域增大，预计宽频和无线服务的费用都将降低，部份是由于商业竞争。 Chapter 2 The Internet and World Wide Web: E-Commerce Infrastructure 电子商务专业英语 2-51 2.4 The World Wide Web Without the World Wide Web, there would be no e-commerce. The invention of the Web brought an extraordinary expansion of digital services to millions of amateur computer users, including color text and pages, formatted text, pictures, animations, video, and sound. In short, the Web makes nearly all the rich elements of human expression needed to establish a commercial marketplace available to nontechnical computer users worldwide. 没有万维网，就不会有电子商务。万维网的发明带来了为数以百万计业的业余计算机使用者提供的数字化服务的非常扩展,包括彩色文本和网页、格式化文本、图片、动画、视频和声音。简而言之，万维网使建立商业化市场必需的人类表达方式的几乎所有丰富要素对非技术计算机使用者成为可能。 Chapter 2 The Internet and World Wide Web: E-Commerce Infrastructure 电子商务专业英语 2-52 2.4.1 Hypertext Web pages can be accessed through the Internet because the Web browser software operating your PC can request Web pages stored on an Internet host server using the HTTP protocol. Hypertext is a way of formatting pages with embedded links that connect documents to one another, and that also link pages to other objects such as sound, video, or animation files. When you click on a graphic and a video clip plays, you have clicked on a hyperlink. For example, when you type a Web address in your browser such as http://www.sec.gov, your browser sends an HTTP request to the sec.gov server requesting the home page of sec.gov. 2.4.1 超文本 因为操个人计算机的网络浏览器软件能使用HTTP协议请求被储存在因特网主机服务器上的一个网页,所以能通过因特网访问万维网网页。超文本是使用嵌入式链接形成格式化网页的一种方法，这些链接将文档彼此联结，而且将网页链接到其他对象如 声音、视频或动画文件。 当你点击一个图形和一个视频剪辑播放按钮的时候,你在点击一个超链接。例如，当你在浏览器中键入一个网址，如 http://www.sec.gov 的的时候,你的浏览器对sec.gov 服务器发出一个HTTP请求，请求 sec.gov的首页。 Chapter 2 The Internet and World Wide Web: E-Commerce Infrastructure 电子商务专业英语 2-53 HTTP is the first set of letters at the start of every Web address, followed by the domain name. The domain name specifies the organization’s server computer that is housing the document. Most companies have a domain name that is the same as or closely related to their official corporate name. The directory path and document name are two more pieces of information within the Web address that help the browser track down the requested page. Together, the address is called a Uniform Resource Locator, or URL. When typed into a browser, a URL tells it exactly where to look for the information. HTTP是每个网址的第一个字母组合，位于网址的开始位置,紧跟着它的是域名。域名限定收藏文件的组织服务器计算机。大多数公司有一个与其官方公司名字相同或接近的域名。目录路径和文件名在网络址里是两个出现较多的信息，帮助浏览器捕捉被请求的网页。同时，网址叫做统一资源定位符号,或URL。当把网址键入一个浏览器内时，URL准确分辨到哪里找寻数据。 Chapter 2 The Internet and World Wide Web: E-Commerce Infrastructure 电子商务专业英语 2-54 The most common domain extensions currently available and officially sanctioned by ICANN are shown in the list below. Countries also have domain names such as .uk, .au, and .fr (United Kingdom, Australia, and France). Also shown in the list below are recently approved top-level domains .biz and .info, as well as new domains under consideration. In the near future, this list will expand to include many more types of organizations and industries. 当前可以使用的最通用的、并被因特网域名与地址管理委员会正式认可的域扩展名见下面列表。国家也有域名如 .uk、.au和.fr(英国、澳洲和法国)。在下面列表中还有最近被核准顶级.biz和.info和正在考虑的域。在不久的将来，这个列表还将扩大到包括更多类型的组织和工业。 Chapter 2 The Internet and World Wide Web: E-Commerce Infrastructure 电子商务专业英语 2-55 2.4.2 Markup Languages Although the most common Web page formatting language is HTML, the concept behind document formatting actually had its roots in the 1960s with the development of Generalized Markup Language (GML). SGML. In 1986, the International Standards Organization adopted a variation of GML called Standard Generalized Markup Language, or SGML. The purpose of SGML was to help very large organizations format and categorize large collections of documents. The advantage of SGML is that it can run independent of any software program but, unfortunately, it is extremely complicated and difficult to learn. Probably for this reason, it has not been widely adopted. 2.4.2 置标语言 虽然最常见的网页格式化语言是HTML,实际上文档格式的概念在20世纪60年代随着通用置标语言(GML)的发展就形成了。 SGML。在1986年，国际标准组织正式通过了GML的一种变体叫做标准通用置标语言,或SGML。SGML的目标是帮助特大型组织对大量文档格式化并归类。SGML的优点是它能独立于任何软件程序运行，但不幸的是，它极端复杂和难学。或许因为这个理由，它没有被广泛地采用 Chapter 2 The Internet and World Wide Web: E-Commerce Infrastructure 电子商务专业英语 2-56 HTML. HTML (HyperText Markup Language) is a GML that is relatively easy to use. HTML provides Web page designers with a fixed set of markup “tags” that are used to format a Web page. When these tags are inserted into a Web page, they are read by the browser and interpreted into a page display. You can see the source HTML code for any Web page by simply clicking on the “Page Source” command found in all browsers. HTML。HTML(超文本链接标示语言)是相对容易使用的一种GML。HTML为网页设计者提供一组固定的标示“标签”用于格式化个网页。当这些标签被插入一个网页之中时,他们被浏览器阅读并翻译为网页显示。你可以看见任何网页的HTML源代码，只需点击一下所有浏览器中都能找到的 "网页源文件"指令。 Chapter 2 The Internet and World Wide Web: E-Commerce Infrastructure 电子商务专业英语 2-57 XML. Extensible Markup Language (XML) takes Web document formatting a giant leap forward. XML is a new markup language specification developed by the W3C (the World Wide Web Consortium). XML is a markup language like HTML, but it has very different purposes. Whereas the purpose of HTML is to control the “look and feel” and display of data on the Web page, XML is designed to describe data and information. XML。可扩展标示语言(XML)使网络文件格式化发生了一次巨大的飞跃。XML是由万维网联合会开发的一种新置标语言规范。XML是像HTML一样的一种置标语言，但是它又有非常不同的目的。XML是用于描述数据和信息,而HTML的目的是控制"表现与感觉" 并将数据在网页上显示。 Chapter 2 The Internet and World Wide Web: E-Commerce Infrastructure 电子商务专业英语 2-58 2.4.3 Web Servers And Clients We have already described client/server computing and the revolution in computing architecture brought about by client/server computing. You already know that a server is a computer attached to a network that stores files, controls peripheral devices, interfaces with the outside world—including the Internet—and does some processing for other computers on the network. But what is a Web server? Web server software refers to the software that enables a computer to deliver Web pages written in HTML to client machines on a network that request this service by sending an HTTP request. 2.4.3 网络服务器及客户机 我们已经描述了客户机/服务器计算技术及其在计算机技术结构中引起的革命。你已经知道服务器是一个联接到网络的计算机，用于储存文件、控制外设、与外界——包括因特网接口，且为网络上的其他计算机进行一些处理。 但什么是网络服务器？网络服务器软件是一种使计算机能够向网上客户机传递HTML网页的软件，而客户机通过发出HTTP请求申请这种服务 Chapter 2 The Internet and World Wide Web: E-Commerce Infrastructure 电子商务专业英语 2-59 Aside from responding to requests for Web pages, all Web servers provide some additional basic capabilities such as the following: Security services—These consist mainly of authentication services that verify that the person trying to access the site is authorized to do so. For Web sites that process payment transactions, the Web server also supports Secure Sockets Layer (SSL), the Internet protocol for transmitting and receiving information securely over the Internet. When private information such as names, phone numbers, addresses, and credit card data need to be provided to a Web site, the Web server uses SSL to ensure that the data passing back and forth from the browser to the server is not compromised. File Transfer Protocol (FTP)—This protocol allows users to transfer files to and from the server. Some sites limit file uploads to the Web server, while others restrict downloads, depending on the user’s identity. 除了回应网页请求之外，所有的网络服务器还提供一些附加的基本能力，例如下列各项: 安全服务——主要由认证服务组成，确认人们试图对网站进行的访问是经过授权的。对于处理支付交易的网站，网络服务器也支持加密套接字协议层(SSL)——用于在因特网上安全地传输与接收信息的因特网协议。当私人信息如姓名、电话号码、地址和信用卡数据等需要向一个网站提供时，网络服务器使用SSL确保从浏览器到服务器来回传递的数据不被损害。 文件传输协议(FTP)——这个协议允许使用者从服务器来回移动文件。根据使用者的身份不同，一些网站限制文件上传到网络服务器,而其他网站限制下载。 Chapter 2 The Internet and World Wide Web: E-Commerce Infrastructure 电子商务专业英语 2-60 Search engine—Just as search engine sites enable users to search the entire Web for particular documents, search engine modules within the basic Web server software package enable indexing of the site’s Web pages and content, and permit easy keyword searching of the site’s content. When conducting a search, a search engine makes use of an index, which is a list of all the documents on the server. The search term is compared to the index to identify likely matches. Data capture—Web servers are also helpful at monitoring site traffic, capturing information on who has visited a site, how long the user stayed there, the date and time of each visit, and which specific pages on the server were accessed. This information is compiled and saved in a log file, which can then be analyzed by a user log file. By analyzing a log file, a site manager can find out the total number of visitors, average length of each visit, and the most popular destinations, or Web pages. 搜索引擎——正如搜索引擎网站使用户能够为特殊的文件搜寻整个万维网,基本网络服务器软件包中的搜寻引擎模块允许对网站的网页和内容进行索引,并允许网站内容的关键词搜索。当进行搜寻时,搜索引擎使用索引, 索引是服务器上所有文件的列表。将搜寻项与索引进行比较，确定可能的匹配。 数据捕获——网络服务器还有助于监测网站访问量，捕获有关谁访问某个网站、用户在那里停留多久、每次访问的日期和时间、和服务器上哪个特定网页被存取等信息。这个信息被汇编并保存在一个日志文件中,然后能通过用户日志文件进行分析。通过分析一个日志文件，网站管理员能找出访客总数、平均访问时间长度和最流行的目的地或网页。 Chapter 2 The Internet and World Wide Web: E-Commerce Infrastructure 电子商务专业英语 2-61 The term Web server is sometimes also used to refer to the physical computer that runs Web server software. Leading manufacturers of Web server computers are IBM, Compaq, Dell, and Hewlett Packard. Although any personal computer can run Web server software, it is best to use a computer that has been optimized for this purpose. To be a Web server, a computer must have the Web server software described above installed and be connected to the Internet. Every Web server machine has an IP address. 术语网络服务器有时也被用于指运行网络服务器软件的实际计算机。网络服务器计算机的领先制造商是IBM(国际商用机器公司)、Compaq(康柏)、Dell(戴尔)和Hewlett Packard(惠普)。虽然任何个人计算机都能运行网络服务器软件，但是最好使用一部为这个目的最佳化的计算机。作为一个网络服务器,一部计算机必须安装上述网络服务器软件且连接到因特网。 Chapter 2 The Internet and World Wide Web: E-Commerce Infrastructure 电子商务专业英语 2-62 A Web client, on the other hand, is any computing device attached to the Internet that is capable of making HTTP requests and displaying HTML pages. The most common client is a Windows PC or Macintosh, with various flavors of UNIX machines a distant third. However, the fastest growing category of Web clients are not computers at all, but personal digital assistants (PDAs) such as the Palm and HP Jornada, and cellular phones outfitted with wireless Web access software. In general, Web clients can be any device—including a refrigerator, stove, home lighting system, or automobile instrument panel—capable of sending and receiving information from Web servers. 另一方面，网络客户机是指任何一种联接到因特网、能够发出HTTP请求并显示网页的计算装置。最常见的客户机是采用Windows操作系统的个人计算机或麦金托什机,各种不同风格的UNIX机远远排在第三。然而，增长速度最快的一类网络客户机并不是计算机,而是个人数字助理(PDA)例如Palm和HP Jornada（掌上电脑）以及配备无线网络访问软件的蜂窝电话。总之，网络客户机可以是任何装置——包括电冰箱、加热器、家用照明系统或汽车仪表盘——只要它能从网络服务器发送并接收信息。 Chapter 2 The Internet and World Wide Web: E-Commerce Infrastructure 电子商务专业英语 2-63 2.4.4 Web Browsers The primary purpose of Web browsers is to display Web pages, but browsers also have added features, such as e-mail and newsgroups (an online discussion group or forum). Currently 94% of Web users use either Internet Explorer or Netscape Navigator, but recently some new browsers have been developed that are beginning to attract attention. The browser Opera is becoming very popular because of its speed—it is currently the world’s fastest browser—and because it is much smaller than existing browsers (it can almost fit on a single diskette). It can also remember the last Web page you visited, so the next time you surf, you can start where you left off. And like the big two, you can get it for free; the catch is that you have to watch blinking ads in one corner, or pay $40 for the ad-free version of Opera. 网络浏览器的主要目是显示网页，但浏览器也有更多的功能, 例如电子邮件和新闻讨论组(在线讨论组或论坛)。 目前，94%的网络用户使用Internet Explorer或Netscape Navigator浏览器，但是最近已开发出的一些新浏览器开始吸引人们的注意力。Oprea浏览器正在变得非常流行，因为它的速度——它是目前世界上最快的浏览器，而且因为它比现有浏览器小得多(它几乎可以装在一张软盘上)。它也能记得你访问过的最后一个网页,因此下回漫游时,你能从你停止的地方开始。而且像那两个大浏览器一样,你能免费得到它；其陷阱是你不得不看一个角落中可恶的广告,否则要支付40美元购买无广告版。 Chapter 2 The Internet and World Wide Web: E-Commerce Infrastructure 电子商务专业英语 2-64 The browser NeoPlanet is also gaining new fans, primarily because of the 500+ skins, or design schemes, that come with it. Using skins, you can design the browser to look and sound just the way you’d like it to, rather than being limited to the standard look provided by Navigator and Internet Explorer. However, NeoPlanet requires Internet Explorer’s technology in order to operate, so you must also have IE installed on your computer. 浏览器NeoPlanet也正在获得新的爱好者,主要因为它带有500多套界面或设计方案。使用不同界面,你能根据你喜欢看或听的方式设计浏览器，而不是被限于Netscape Navigator和Internet Explorer浏览器提供的标准外观。然而, NeoPlanet 需要Internet Explorer的技术来运行,因此你也必须在计算机上安装IE。 Chapter 2 The Internet and World Wide Web: E-Commerce Infrastructure 电子商务专业英语 2-65 英语专业词汇的构成 一、派生词(derivation) 1．前缀 采用前缀构成的单词在计算机专业英语中占了很大比例，通过下面的实例可以了解这些常用的前缀构成的单词。 multi-多 hyper-超级 super 超级 multiprogram 多道程序 hypercube 超立方 superhighway 超级公路 multimedia 多媒体 hypercard 超级卡片 superpipline 超流水线 multiprocessor 多处理器 hypermedia 超媒体 superscalar 超标量 multiplex 多路复用 hypertext 超文本 superset 超集 multiprotocol 多协议 hyperswitch 超级交换机 superclass 超类 inter-相互、在...间 micro-微型 tele-远程的 interface接口、界面 microprocessor 微处理器 telephone 电话 interlace 隔行扫描 microkernel 微内核 teletext 图文电视 interlock 联锁 microcode 微代码 telemarketing 电话购物 internet互联网络(因特网) microkid 微机迷 telecommuting家庭办公 interconnection 互联 microchannel 微通道 teleconference远程会议 Chapter 2 The Internet and World Wide Web: E-Commerce Infrastructure 电子商务专业英语 2-66 英语专业词汇的构成 一、派生词(derivation) 1．前缀 单词前缀还有很多，其构成可以同义而不同源(如拉丁、希腊)，可以互换，例如： multi, poly 相当于many 如: multimedia多媒体, polytechnic各种工艺的 uni, mono 相当于single 如: unicode统一的字符编码标准, monochrome单色 bi, di 相当于 twice 如: binomial 二项式，dibit双位 equi,iso 相当于equal 如: equality等同性, isochromatic等色的, simili, homo 相当于same 如: similarity类似, homogeneous同类的 semi,hemi 相当于half 如: semiconductor半导体, hemicycle半圆形 hyper, super 相当于over 如: hypertext超文本, supercomputer超级计算机 Chapter 2 The Internet and World Wide Web: E-Commerce Infrastructure 电子商务专业英语 2-67 2．后缀 后缀是在单词后部加上构词结构，形成新的单词。如: -scope 探测仪器 -meter 计量仪器 -graph 记录仪器 microscope显微镜 barometer 气压表 tomograph X线体层照相 telescope 望远镜 telemeter 测距仪 telegraph 电报 spectroscope 分光镜 spectrometer 分光仪 spectrograph 分光摄像仪 -able可能的 -ware 件(部件) -ity 性质 enable 允许、使能 hardware 硬件 reliability 可靠性 disable 禁止、不能 software 软件 availability 可用性 programmable 可编程的 firmware 固件 accountability 可核查性 portable 便携的 groupware 组件 integrity 完整性 scalable 可缩放的 freeware 赠件 confidentiality 保密性 Chapter 2 The Internet and World Wide Web: E-Commerce Infrastructure 电子商务专业英语 2-68 二、复合词(compounding) 复合词是科技英语中另一大类词汇，其组成面广，通常分为复合名词、复合形容词、复合动词等。复合词通常以小横杠“-”连接单词构成，或者采用短语构成。有的复合词进一步发展，去掉了小横杠,并经过缩略成为另一类词类，即混成词。复合词的实例有: -based基于，以……为基础 -centric 以……为中心的 rate-based 基于速率的 client-centric 以客户为中心的 credit-based 基于信誉的 user-centric 以用户为中心的 file-based 基于文件的 host-centered 以主机为中心的 Windows-based 基于Windows的 -oriented 面向……的 -free 自由的，无关的 object-oriented 面向对象的 lead-free 无线的 market-oriented 市场导向 jumper-free 无跳线的 process-oriented 面向进程的 paper-free 无纸的 thread-oriented 面向线程的 charge-free 免费的 info-信息，与信息有关的 envent-事件的 info-channel 信息通道 envent-driven 事件驱动的 info-tree 信息、树 envent-oriented 面向事件的 info-world 信息世界 event-based 基于事件的 info-sec 信息安全 Chapter 2 The Internet and World Wide Web: E-Commerce Infrastructure 电子商务专业英语 2-69 三、混成词(blending) 混成词不论在公共英语还是科技英语中也大量出现，也有人将它们称为缩合词（与缩略词区别）、融会词，它们多是名词，也有地方将其作为动词用，对这类词汇可以通过其构词规律和词素进行理解。这类词汇将两个单词的前部拼接、前后拼接或者将一个单词前部与另一词拼接构成新的词汇，实例有： brunch (breakfast + lunch) 早中饭 smog (smoke +fog) 烟雾 codec (coder+decoder) 编码译码器 compuser (computer+user) 计算机用户 transeiver (transmitter+receiver) 收发机 syscall (system+call) 系统调用 mechatronics (mechanical+electronic) 机械电子学 calputer (calculator+computer) 计算器式电脑 Chapter 2 The Internet and World Wide Web: E-Commerce Infrastructure 电子商务专业英语 2-70 四、缩略词(shortening) 1．压缩和省略 将某些太长、难拼、难记、使用频繁的单词压缩成一个短小的单词，或取其头部、或取其关键音节。如: f1u=influenza 流感 1ab=laboratory 实验室 math=mathematics 数学 iff=if only if 当且仅当 rhino=rhinoceros 犀牛 ad=advertisement 广告 2．缩写 (acronym) 将某些词组和单词集合中每个实意单词的第一或者首部几个字母重新组合，组成为一个新的词汇，作为专用词汇使用。在应用中它形成三种类型，即: 1) 通常以小写字母出现，并作为常规单词 flops (floating-point Operation Per Second) 每秒浮点运算次数 spool (simultaneous peripheral operation on line) 假脱机 2) 以大写字母出现，具有主体发音音节 BASIC (Beginner's All-purpose Symbolic Instruction Code) 初学者通用符号指令代码 FORTRAN (Formula Translation) 公式翻译(语言) COBOL (Common Business Oriented Language) 面向商务的通用语言 3) 以大写字母出现，没有读音音节，仅为字母头缩写 RISC (Reduced Instruction Set Computer) 精简指令集计算机 CISC (Complex Instruction Set Computer) 复杂指令集计算机 ADE (Application Development Environment) 应用开发环境 Chapter 2 The Internet and World Wide Web: E-Commerce Infrastructure 电子商务专业英语 2-71 五、借用词 借用词一般来自厂商名、商标名、产品代号名、发明者名、地名等，它通过将普通公共英语词汇演变成专业词意而实现。有的则是将原来已经有的词汇赋予新的含义。例如： woofer 低音喇叭 tweeter 高音喇叭 flag标志、状态 cache 高速缓存 semaphore 信号量 firewall 防火墙 mailbomb 邮件炸弹 scratch pad 高速缓存 fitfall 专用程序入口 Chapter 2 The Internet and World Wide Web: E-Commerce Infrastructure $$