Chapter 7 The Internet, Intranets, and Extranets

Chapter 7The Internet, Intranets,

and Extranets

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Learning Objectives

When you finish this chapter, you will

Know what the Internet is.Know the features for information exchange that can be conducted over the World Wide Web. Understand how the Web facilitates electronic commerce. Be able to generate basic ideas for new business ventures utilizing the Web.Appreciate the major risks and limitations of using the Web for business activities.

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Enterprise Networking and Internetworking

Enterprise Networking

An arrangement of the organization’s hardware,software, network, and data resources to put morecomputing power on the desktop and create a company wide network linking many smaller networks.

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Enterprise Networking and Internetworking

Internetworking

The linking of separate networks, each of whichretains its own identity, into an interconnectednetwork.

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What is the Internet?

The Development of the Internet

ARPANET (Advanced Research Project Agency Network ) was an open system designed for the free flow of information, but available only to members of academic institutions and some of the defense industry.

U.S. government decided to split the network into a civilian one and a military one.

Civilian network became the Internet

Internet is now a network of networks.

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Figure 7.1 The Internet connects millions of servers.

(Internet is not, and cannot, be controlled by anyone)

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Internet Service Provider

A commercial organization with a permanentthat sells temporary connections to subscribers.

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TCP/IP To join the Internet, an existing network

needs only to pay a small registration fee and agree to certain standard based on the TCP/IP reference model.

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TCP/IPApplication

Presentation

Session

Transport

Network

Data Link

Physical

Application

Transport

Internet

Network Interface

OSI TCP/IP

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TCP/IP

Application

Transport

InternetProtocol

NetworkInterface

(transmission control protocol)

Datagrams

Segment

Message

ftp, http, smtp,dns, …

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Growth of the InternetNumber of servers

From a few hundred in 1993, to more than 43,000,000 by mid-1999

Number of usersMore than 200 million; increased rapidly during 1999

Commercial Online ServicesCompanies like America Online provide “online” service to paying subscribers on their private networks.

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Figure 7.2 World growth of the Internet

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Figure 7.3 The number of Internet domain servers continues to grow

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Internet Technology and Service

Client/Server Technology

ServerClient

Web Browser

e-mailWeb pages

request

response

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Electronic Mail (E-Mail)

Internet Tools for Communication

Person to person messaging; document sharing

E-Mail Address

identifier@domain name

unique node on the internet

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Internet Domains

A domain name is assigned to each IP address.

Internet servers are grouped into different domains. (Function, Location)

Domain names are registered by one of a group of companies authorized to assign unique names.


17Figure 7.4 Examples of Internet address suffixes


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UseNet NewsGroups


Usenet newsgroups are worldwide discussion groupsin which people share information and ideas on a definedtopic. Discussion takes place in large electronic bulletinboards where anyone can post messages for others to read.

ListServ

On-line groups using e-mail broadcast from mailing listservers for discussions and messaging.

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Chatting


Chatting allows two or more people who are simultaneouslyconnected to the Internet to hold live, interactiveconversations.

Instant Messaging

Chat service that allows participants to create their ownprivate chat channels so that a person can be alerted whenever someone on his or her private list is on-line toinitiate a chat session with that particular individual.

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Telnet


Network tool that allows someone to log on to onecomputer system while doing work on another.

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Information Retrieval on the Internet

FTP (File transfer protocol)

Tool for retrieving and transferring files from a remotecomputer

Gopher

A tool that enables the user to locate information storedon internet servers through a series of easy-to-use,hierarchical menus

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The World Wide Web

The World Wide Web is at the heart of the explosion in the business use of the Net.

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The World Wide Web

Hypertext transfer protocol (HTTP)The communication standard used to transfer pages on the Web. Defines how messages are formatted and transmitted.

Hypertext Mark-Up Language (HTML)Code for tagging Web files for display

BrowsersSoftware to access the Web

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The World Wide Web

Home Page and Web Side

A WWW text and graphical screen display that welcomesthe user and explains the organization that has establishedthe page

Home Page

Web Page

Web Page

Web Page

Web PageWeb Side

Webmaster

in charge

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The World Wide Web

Uniform Resource Locator (URL)

The address of a specific resource on the Internet.

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The World Wide Web

Creating Web FilesHTML

System of standardized “tags” that format elements text, graphics, and animation

Web page editorsTranslate well-known or intuitive commands into code

Java, ActiveX, and XMLWeb scripting languages

Common Gateway Interfaces (CGI) and FormsAllow a computer that is accessing a particular Web site to have some similar functions

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The World Wide Web

Figure 7.5 How a CGI works

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The World Wide Web

Searching for Information on the Web

Search engine: A tool for locating specific sitesor information on the Internet.

Shopping bot: Software with varying levels ofbuild-in intelligence to help electronic commerceshoppers locate and evaluate products or servicethey might wish to purchase.ex:www.mysimon.com

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The World Wide Web

Searching for Information on the Web

Broadcast and “Push” Technology (Channels)

Push Technology: Method of obtaining relevant informationon networks by having a computer broadcast information directly to the user based on prespecified interests

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Intranets and Extranets

IntranetA within-organization computer network that uses Internet technologies to communicate

Extranet Uses Internet technologies to facilitate communication and trade between an organization and its business partners, such as suppliers

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Intranet Technology

Firewalls: Hardware and software placed betweenan organization’s internal network and an externalnetwork to prevent outsiders from invadingprivate networks.

Firewall Server

Client

Client

Client

Internet

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Figure 7.6 An intranet, an extranet, and the Internet from an individual user’s perspective

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Figure 7.7 Internet, intranet, and extranet potential for productivity enhancement

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Intranets

Figure 7.8 Savings resulting from the Internet, intranet, and extranet e-commerce

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Establishing a Web Site

Site Name

Points of Presence ( 入網點 )

Line Capacity

Site Maintenance

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Establishing a Web Site

Figure 7.9 Transfer times of a 10-MB file by different media

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Business on the Internet

Business-to-Business Trading $43 billion - 1998 -> $1.3 trillion 9% by 2003 in USA

Electronic Data Interchange

Exchanges and Auctions ( 拍賣 )

E-catalogs

XML and EDI

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Business-to-Consumer TradingAdvertising

PortalsFree Internet applications

E-ShoppingE-PaymentAuctions and reverse auctionsSelling contentSelling softwareData pushStock trading for all

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Figure 7.10 Web-shopping benefits

The additional benefits to organization?

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Figure 7.11 Estimated unique visitors to individual Web sites during 8/09/99-8/15/99


Web Demographics

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Business Considerations

Web Costs

The least costly sites are those constructed simply to showcase the company’s products or services.

The most expensive sites are those designed to enable electronic commerce. (B2B>B2C)

Electronic commerce server software

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Electronic Commerce Server Software

Software that provides functions essential for running e-commerce Web sites, such as setting up electronic catalogs and storefronts and processing customer purchases.

Ex: Commerce Server and BizTalk Server Websphere Commerce Suite

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Figure 7.12 The average cost to a company offering a Web site for electronic commerce

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Rules for Successful Web Sites

Target the right customers Ex: Pay for ad banners and links at sides

Own the customer’s total experience

Ex: Marketing to one

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Let customers help themselves

Ex: get information any time including after-the-sale information

Help customer do their job

Ex: Free ASP

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Personalize the service

Be proactive

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Figure 7.13 Do’s and Don’ts in Web site construction for commercial purposes

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Risks to OrganizationsComputer virusesInterception of passwords and codes by an unauthorized hackerInterception of charge account numbers - encryptionIllegal or socially objectionable use of a sitePotential misrepresentation

Risks to ConsumersEavesdropping and interception Misrepresentation

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Next Generation Internet: Broadband andInternet2

Internet2

Research network with new protocols and transmission speeds that provides an infrastructure for supportinghigh bandwidth Internet applications

University Corporation for Advanced Internet Development(UCAID)NASADARPANext Generation Internet (NGI)

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GigaPoPs 全名 Gigabit capacity Point of Presence ，是第二代網際網路的區域連結與服務中心。它的配備包含一個或多個高容量、功能先進的封包 (Packet) 資料轉接路由器 (Router ) ，至少能夠支援 OC-12 (622 Mbps) 的傳輸速度。事實上，它結合了許多網路技術，包括SONET 、非同步傳輸模式 (ATM ) 、網際網路通訊協定 (IP ) ( 含 IPv4 和網際網路通訊協定第6版 (IPv6) ) 、路由協定 (MOSPF ， BGP) 、 QoS協定 (RSVP ， RTP) 等。

GigaPoP 又稱 I2SC (Internet2 Service Center) ，為分散於全美各地的地區性高效能網路訊務集合中樞點，具有 Gbps 交換及路由的功能，可連接各式樣的服務介面，並可連接網路服務供應商以提供網際網路 (Internet) 原有的服務。

gigaPoPs

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Quality of Service Level

Under Internet2 different types of packets could beassigned different levels of priority as they travel overthe network.

Documents

Chapter 7 The Internet, Intranets, and Extranets