计算机网络专业外文文献

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The NetWorks......................................................................................................................................2

Birth of the Net............................................................................................................................2

How the Web Works....................................................................................................................2

Some Web History.......................................................................................................................3

Understanding Web Addresses....................................................................................................4

Domain Names............................................................................................................................5

About Modem.............................................................................................................................6

Decoding Error Messages.........................................................................................................10

Web Browsers............................................................................................................................12

网 络..................................................................................................................................................14

网络的诞生...............................................................................................................................15

网络是如何工作的...................................................................................................................15

一些网络的历史.......................................................................................................................16

网 址.........................................................................................................................................16

域 名.........................................................................................................................................17

关于调制解调器.......................................................................................................................18

加 速..........................................................................................................................................19

DNS 失败检索..................................................................................................................23

主机不可用：...................................................................................................................23

主机未知：.......................................................................................................................23

不能定位主机...................................................................................................................23

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The NetWorks

Birth of the Net

The Internet has had a relatively brief, but explosive history so far. It grew out of an experiment

begun in the 1960's by the U.S. Department of Defense. The DoD wanted to create a computer

network that would continue to function in the event of a disaster, such as a nuclear war. If part of

the network were damaged or destroyed, the rest of the system still had to work. That network was

backbone service.

NSFNET grew rapidly as people discovered its potential, and as new software applications

were created to make access easier. Corporations such as Sprint and MCI began to build their own

networks, which they linked to NSFNET. As commercial firms and other regional network

providers have taken over the operation of the major Internet arteries, NSF has withdrawn from

the backbone business.

　　NSF also coordinated a service called InterNIC, which registered all addresses on the Internet

so that data could be routed to the right system. This service has now been taken over by Network

Solutions, Inc., in cooperation with NSF.

How the Web Works

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computer, web browser software, a connection to an Internet service provider, computers called

servers that host digital data and routers and switches to direct the flow of information.

　 　 The Web is known as a client-server system. Your computer is the client; the remote

computers that store electronic files are the servers. Here's how it works:

　 　 Let's say you want to pay a visit to the the Louvre museum website. First you enter the

address or URL of the website in your web browser (more about this shortly). Then your browser

requests the web page from the web server that hosts the Louvre's site. The Louvre's server sends

electronic files on the Web to be linked so you can easily jump between them. On the Web, you

navigate through pages of information based on what interests you at that particular moment,

　　To access the Web you need web browser software, such as Netscape Navigator or Microsoft

Internet Explorer. How does your web browser distinguish between web pages and other files on

the Internet? Web pages are written in a computer language called Hypertext Markup Language or

HTML.

Some Web History

The World Wide Web (WWW) was originally developed in 1990 at CERN, the European

Laboratory for Particle Physics. It is now managed by The World Wide Web Consortium, also

known as the World Wide Web Initiative.

　　The WWW Consortium is funded by a large number of corporate members, including AT&T,

Adobe Systems, Inc., Microsoft Corporation and Sun Microsystems, Inc. Its purpose is to promote

researchers by providing software for scientific modeling, analysis, and visualization. The World

Wide Web was an obvious way to fulfill that mission. NCSA Mosaic, one of the earliest web

browsers, was distributed free to the public. It led directly to the phenomenal growth of the World

Wide Web.

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Understanding Web Addresses

You can think of the World Wide Web as a network of electronic files stored on computers all

around the world. Hypertext links these resources together. Uniform Resource Locators or URLs

are the addresses used to locate these files. The information contained in a URL gives you the

ability to jump from one web page to another with just a click of your mouse. When you type a

URL into your browser or click on a hypertext link, your browser is sending a request to a remote

　　news:rec.gardens.roses

A newsgroup on rose gardening.

　　The first part of a URL (before the two slashes* tells you the type of resource or method of

access at that address. For example:

• http - a hypertext document or directory

• gopher - a gopher document or menu

• ftp - a file available for downloading or a directory of such files

• news - a newsgroup

• telnet - a computer system that you can log into over the Internet

• WAIS* - a database or document in a Wide Area Information Search database

　　Most browsers record URLs that you want to use again, by adding them to a special menu. In

Netscape Navigator, it's called Bookmarks. In Microsoft Explorer, it's called Favorites. Once you

add a URL to your list, you can return to that web page simply by clicking on the name in your

list, instead of retyping the entire URL.

　 　 Most of the URLs you will be using start with http which stands for Hypertext Transfer

Protocol*. http is the method by which HTML files are transferred over the Web. Here are some

other important things to know about URLs:

• A URL usually has no spaces.

• A URL always uses forward slashes (//).

If you enter a URL incorrectly, your browser will not be able to locate the site or resource you

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correctly.

You can find the URL behind any link by passing your mouse cursor over the link. The pointer

will turn into a hand and the URL will appear in the browser's status bar, usually located at the

bottom of your screen.

remember long strings of numbers, the Domain Name System (DNS)* was developed. DNS, a

critical part of the Internet's technical infrastructure*, correlates* a numerical address to a word.

To access the White House website, you could type its number into the address box of your web

browser. But most people prefer to use "www.whitehouse.gov." In this case, the domain name is

whitehouse.gov.

In general, the three-letter domain name suffix* is known as a generic top-level domain and

describes the type of organization. In the last few years, the lines have somewhat blurred* between

these categories.

.com - business (commercial)

.edu - educational

.gov - government

A domain name always has two or more parts separated by dots and typically consists of some

form of an organization's name and the three-letter suffix. For example, the domain name for IBM

is "ibm.com"; the United Nations is "un.org."

If a domain name is available, and provided it does not infringe* on an existing trademark, anyone

and .store. When that will actually happen is anybody's guess.

To check for, or register a domain name, type it into the search box.

It should take this form: myname.com

In addition to the generic top-level domains, 244 national top-level domains were established for