Technology Guide 5.ppt

1、Technology Guide 5,1,Technology Guide 5,Information Technology For Management 4th Edition Turban, McLean, Wetherbe Lecture Slides by A. Lekacos, Stony Brook University John Wiley & Sons, Inc.,The Internet and the Web,Technology Guide 5,2,The Internet,ARPAnet (Advance Research Project Agency) 1969 fo

2、r DOD Defense related companies & universities 1970s TCP/IP became the standard during the 1970s (Unix) Most companies & universities 1980s All connected networks became TCP/IP based during 80s NSF in 1986 6 Super computers as the backbone Individual users were allowed access in 1992,The Internet (“

3、the Net”) is a network that connects hundreds of thousands of internal organizational computer networks worldwide. Participating computer systems, called nodes, include PCs, local area networks, databases, and mainframes. A node may include several networks of an organization, possibly connected by

4、a wide area network. The main network that links the nodes is referred to as the backbone, a fiber-optic network currently operated mainly by telecommunications companies.,Technology Guide 5,3,Next-Generation Internet,Internet2 is a collaborative effort to develop advanced Internet technologies and

5、applications. The primary goals of Internet2 are to create a leading-edge network capability to enable revolutionary Internet applications; and ensure the rapid transfer of new network services and applications. It will use part of vBNS as a backbone for providing high-speed connectivity. Very-high-

6、speed Backbone Network Service (vBNS) is a high-speed network designed to support the Internet2 and the government-sponsored Next-Generation Internet (NGI) initiative TCP/IP became the standard during the 1970s (Unix).,The broad goals of the NGI initiative are to research and develop advanced end-to

7、-end networking technologies, focusing primarily on reliability, robustness, security, quality of service guarantees for multicasting and video, and bandwidth allocation. In other words, the NGI initiative aims to create an Internet that is fast, always on, everywhere, natural, intelligent, easy, an

8、d trusted.,Technology Guide 5,4,Internet Characteristics Accessing the Internet,Connecting via LAN server Connecting via serial line internet protocol/point-to-point protocol (slip/ppp) Connecting via an online service Using the TV as a channel to the internet Internet kiosks,There are several ways

9、to access the Internet. You can access an Internet-connected file server on a LAN. Log onto the Internet using a modem or wireless connections or connection through commercial providers.,Technology Guide 5,5,Internet Characteristics Protocol,Packets represent information that has been divided into s

10、mall portions to be passed through the Internet. Their creation and transmission are governed by TCP/IP to provide for more consistent delivery and control. One member of the TCP/IP family of protocols is Telnet, a service that allows users to connect to computers other than their own and interactiv

11、ely search for files, text, software, and so forth.,Procedures and rules for transferring data across the Internet are called telecommunications protocols. The original participants of the Internet used TCP/IP which is now the Internet Protocol (IP).,Technology Guide 5,6,Internet Characteristics Res

12、ources,Addresses on the internet. Each computer on the Internet has an assigned address, called the IP (Internet Protocol) address, that uniquely identifies and distinguishes it from all other computers. Domain Names. Most computers also have names, which are easier for people to remember than IP ad

13、dresses. These names are derived from a naming system called the domain name system (DNS). URLs. A uniform resource locator (URL) indicates the location (or address) of a Web site you want to visit. The address consists of several parts.,Accessing a resource (file, image, document, etc.) on the Inte

14、rnet.,Technology Guide 5,7,Internet Characteristics Resources,Domain Names. Most computers also have names, which are easier for people to remember than IP addresses. These names are derived from a naming system called the domain name system (DNS).,Technology Guide 5,8,Internet Characteristics Resou

15、rces,URLs. A uniform resource locator (URL) indicates the location (or address) of a Web site you want to visit. The address consists of several parts.,URL = protocol/host computer or IP/path/file,Protocol is http hypertext transfer protocol,Host computer is the domain name IP is actual address,Path

16、 filesystem or directory,server,File is the specific page name (Index, Home, Default),Optional Start page,Technology Guide 5,9,Browsing the Web,The most widely used browsers are: Netscape Navigator Microsoft explorer New browsers: Opera NeoPlanet Ofine browsers enable a user to retrieve pages automa

17、tically from Web sites at predetermined times.,You browse the vast resources of the Internet through the World Wide Web (or “the Web”). The Web is a vast collection of interconnected pages of information that are stored on computers connected to the Internet. It is a system with universally accepted

18、 standards for storing, retrieving, formatting, and displaying information (text, pictures, video, and so on) via a client/server architecture. Documents accessible on the Web contain hyperlinks (links) to other documents. Such links are used to connect documents and are an implementation of hyperte

19、xt.,Technology Guide 5,10,Creating Web Documents,Dynamic HTML (DHTML) eXtensible Markup Language (XML) Virtual Reality Modeling Language (VRML) Java PHP Coldfusion,To write a Web document for the Internet or an intranet, various software languages can be used. The most common is HyperText Markup Lan

20、guage (HTML), which formats documents and incorporates dynamic hypertext links to other documents stored on the same or different computers.,Other Languages,Technology Guide 5,11,Search Tools,Google Yahoo Lycos HotBot WebCrawler Alta Vista Excite,A search engine is a tool that makes your browser mor

21、e effective. It enables you to locate information by using key words in the same way that you would search online library resources,Some Engines,Search engines select pages for inclusion in their databases in two primary ways: Web crawlers traverse the Web automatically, collecting index data on sea

22、rch principles Registration Web developers register their sites,Selection,Many of the documents are transferable from the Internet using le transfer protocol (FTP),Download,Technology Guide 5,12,Communication Tools,Electronic Mail Online Chatting Newsgroups Mailing Lists and Electronic Bulletin Boar

23、ds Portals Internet Telephony Internet Fax,Several communication tools are available on the Internet.,Technology Guide 5,13,Other Internet Tools,Streaming Audio and Video Real-Time Audio and Video Web Services Push Technology Information Filters Clipping Services Web Authoring,Technology Guide 5,14,

24、Internet Tools,Technology Guide 5,15,Technology Guide 5,Copyright 2004 John Wiley & Sons, Inc. All rights reserved. Reproduction or translation of this work beyond that permitted in Section 117 of the 1976 United States Copyright Act without the express written permission of the copyright owner is u

25、nlawful. Request for further information should be addressed to the Permissions Department, John Wiley & Sons, Inc. The purchaser may make back-up copies for his/her own use only and not for distribution or resale. The Publisher assumes no responsibility for errors, omissions, or damages, caused by the use of these programs or from the use of the information contained herein.,