ELC 200 Day 6 Copyright 2010 Pearson

981116501870c39865be6f884bda295c.ppt

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Agenda Questions? n Assignment 1 Not corrected yet, will be corrected, and feedback provided, later today n Assignment 2 posted in Black. Board n Due Tuesday, February 14 @ 9: 35 AM v assignment 2. pdf v n Quiz 1 Feb 17 Chap 1 -4, Open Book, Open Notes v 20 M/C @ 4 points each v 4 short essays @ 5 points each v 1 extra credit question worth 5 points v n Finish Discussion on The Internet and the World Wide Web

Possible Bonus Points Questions n Name and origin of v. What does his name mean? v. What does he look like all v“grown up”? n Name and origin of v Hic Sunt Dracones Copyright © 2010 Pearson Education, Inc. Slide 1 -3

Chapter 3: The Internet and World Wide Web: E-commerce Infrastructure Chapter 3 The Internet and World Wide Web: E-commerce Infrastructure Copyright 2011 Pearson Education, Inc. Copyright © © 2011 Pearson Education, Inc. 2007 Pearson Education, Inc. Slide 1 -4

Client/Server Computing n Powerful personal computers (clients) connected in network with one or more servers n Servers perform common functions for the clients v Storing files, software applications, etc. Copyright © 2011 Pearson Education, Inc. Slide 3 -5

The New Client: The Emerging Mobile Platform n Within a few years, primary Internet access will be through: v. Netbooks & Tablets Designed to connect to wireless Internet n Under 2 lb, solid state memory, 8” displays n $200 -400 $200 for Kindle Fire, $500 -800 for i. Pad 2 n v. Smartphones n Disruptive technology: Processors, operating systems Copyright © 2011 Pearson Education, Inc. Slide 3 -7

Cloud Computing n Firms and individuals obtain computing power and software over Internet v E. g. , Google Apps n Fastest growing form of computing n Radically reduces costs of: v Building and operating Web sites v Infrastructure, IT support v Hardware, software Copyright © 2010 Pearson Education, Inc. Slide 3 -8

The Internet Today n Internet growth has boomed without disruption because of: v. Client/server computing model v Hourglass, layered architecture n Network Technology Substrate n Transport Services and Representation Standards n Middleware Services n Applications Copyright © 2011 Pearson Education, Inc. Slide 3 -10

Internet Network Architecture n Backbone: High-bandwidth fiber-optic cable networks v Private networks owned by a variety of NSPs v Bandwidth: 155 Mbps – 2. 5 Gbps v Built-in redundancy v n IXPs: Hubs where backbones intersect with regional and local networks, and backbone owners connect with one another n CANs: LANs operating within a single organization that leases Internet access directly from regional or national carrier Copyright © 2011 Pearson Education, Inc. Slide 3 -12

Internet Service Providers (ISPs) n Provide lowest level of service to individuals, small businesses, some institutions n Types of service v Narrowband (dial-up) v Broadband n Digital Subscriber Line (DSL) n Cable modem n T 1 and T 3 n Satellite Copyright © 2011 Pearson Education, Inc. Slide 3 -15

Intranets and Extranets n Intranet v. TCP/IP network located within a single organization for communications and processing n Extranet v. Formed when firms permit outsiders to access their internal TCP/IP networks Copyright © 2011 Pearson Education, Inc. Slide 3 -16

Who Governs the Internet? n Organizations that influence the Internet and monitor its operations include: v v v v Internet Architecture Board (IAB) Internet Corporation for Assigned Names and Numbers (ICANN) Internet Engineering Steering Group (IESG) Internet Engineering Task Force (IETF) Internet Society (ISOC) World Wide Web Consortium (W 3 C) International Telecommunications Union (ITU) More information @ http: //www. isoc. org/standards/ Copyright © 2011 Pearson Education, Inc. Slide 3 -17

Insight on Society Government Regulation and Surveillance of the Internet Class Discussion n How is it possible for any government to “control” or censor the Web? n Does the Chinese government, or the U. S. government, have the right to censor content on the Web? n How should U. S. companies deal with governments that want to censor content? n What would happen to e-commerce if the existing Web split into a different Web for each country? Copyright © 2011 Pearson Education, Inc. Slide 3 -18

Internet II: The Future Infrastructure n Limitations of current Internet v Bandwidth limitations v Quality of service limitations Latency n “Best effort” QOS n v Network architecture limitations v Language development limitations n HTML v Wired Internet limitations Copyright © 2011 Pearson Education, Inc. Slide 3 -19

The Internet 2® Project Consortium of 200+ universities, government agencies, and private businesses collaborating to find ways to make the Internet more efficient, faster n http: //www. umaine. edu/it/internet 2/ n Primary goals: n v Create leading edge very-high speed network for national research community v Enable revolutionary Internet applications v Ensure rapid transfer of new network services and applications to broader Internet community Copyright © 2011 Pearson Education, Inc. Slide 3 -20

The Larger Internet II Technology Environment: The First Mile and the Last Mile n GENI Initiative http: //www. geni. net/ v Proposed by NSF to develop new core functionality for Internet n Most significant private initiatives v Fiber optics v Mobile wireless Internet services Copyright © 2011 Pearson Education, Inc. Slide 3 -22

Fiber Optics and the Bandwidth Explosion in the First Mile n “First mile”: Backbone Internet services that carry bulk traffic over long distances n Older transmission lines being replaced with fiberoptic cable n Much of fiber-optic cable laid in United States is “dark”, but represents a vast digital highway that can be utilized in the future v Technology improvement has expanded capacity of existing fiber lines Copyright © 2011 Pearson Education, Inc. Slide 3 -23

Optical Fiber Source: Adapted from Panko, Raymond, Business Data Communications and Networking (3 rd ed. ), Upper Saddle River, NJ: Prentice-Hall, 2001, p. 278. 1 -24

Optical Fiber 1 -25

The Last Mile: Mobile Wireless Internet Access n “Last mile”: From Internet backbone to user’s computer, cell phone, PDA, etc. n Two different basic types of wireless Internet access: 1. Telephone-based (mobile phones, smartphones) 2. Computer network-based Copyright © 2011 Pearson Education, Inc. Slide 3 -26

Telephone-based Wireless Internet Access n Competing 3 G standards v v n GSM: Used world-wide, AT&T, T-Mobile CDMA: Used primarily in U. S. Evolution: v 2 G cellular networks: relatively slow, circuit-switched v 2. 5 G cellular networks: interim networks v 3 G cellular networks: next generation, packet-switched v 3. 5 G (3 G+) v 4 G (Wi. Max, LTE) Copyright © 2011 Pearson Education, Inc. Slide 3 -27

Wireless Local Area Networks (WLANs) n Wi-Fi v n Wi. Max v n High-speed, fixed broadband wireless LAN. Different versions for home and business market. Limited range. High-speed, medium range broadband wireless metropolitan area network Bluetooth v v n Low power, short-range high bandwidth network v n Low-speed, short range connection Short-range, low-power wireless network technology for remotely controlling digital devices Ultra-Wideband (UWB) Zigbee Bonus question? Copyright © 2011 Pearson Education, Inc. Slide 3 -28

Benefits of Internet II Technologies n IP multicasting: v n Enables efficient delivery of data to many locations on a network Latency solutions: v diffserv (differentiated quality of service) n n Guaranteed service levels and lower error rates v n Assigns different levels of priority to packets depending on type of data being transmitted Ability to purchase the right to move data through network at guaranteed speed in return for higher fee Declining costs Copyright © 2011 Pearson Education, Inc. Slide 3 -30

Hypertext n Text formatted with embedded links v. Links connect documents to one another, and to other objects such as sound, video, or animation files n Uses Hypertext Transfer Protocol (HTTP) and URLs to locate resources on the Web v Example URL http: //megacorp. com/content/features/082602. html Copyright © 2011 Pearson Education, Inc. Slide 3 -32

Markup Languages Generalized Markup Language (GML) – 1960 s n Standard Generalized Markup Language (SGML) –GML variation, 1986 n n Hypertext Markup Language (HTML) Fixed set of pre-defined markup “tags” used to format text v Controls look and feel of Web pages v n e. Xtensible Markup Language (XML) New markup language specification developed by W 3 C v Designed to describe data and information v Tags used are defined by user v Copyright © 2011 Pearson Education, Inc. Slide 3 -33

Web Servers and Web Clients n Web server software: Enables a computer to deliver Web pages to clients on a network that request this service by sending an HTTP request v Apache and Microsoft IIS v Basic capabilities: Security services, FTP, search engine, data capture v n Web server v v n Can refer to Web server software or physical server Specialized servers: Database servers, ad servers, etc. Web client: v Any computing device attached to the Internet that is capable of making HTTP requests and displaying HTML pages Copyright © 2011 Pearson Education, Inc. Slide 3 -34

Web Browsers n Primary purpose to display Web pages n Internet Explorer and Firefox dominate the market n Other browsers include: v Netscape v Opera v Safari (for Apple) v Google Chrome Copyright © 2011 Pearson Education, Inc. Slide 3 -35

Development of the Web n 1989– 1991: Web invented Tim Berners-Lee at CERN v HTML, HTTP, Web server, Web browser v n 1993: Mosaic Web browser w/ GUI Andreesen and others at NCSA v Runs on Windows, Macintosh, or Unix v n 1994: Netscape Navigator, first commercial Web browser v Andreessen, Jim Clark n 1995: Microsoft Internet Explorer n The Browser wars begin! Copyright © 2011 Pearson Education, Inc. Slide 3 -36

The Internet and Web: Features n Internet and Web features on which the foundations of e-commerce are built include: v E-mail v Instant messaging v Search engines v Intelligent agents (bots) v Online forums and chat v Streaming media v Cookies Copyright © 2011 Pearson Education, Inc. Slide 3 -37

E-mail n Most used application of the Internet n Uses series of protocols for transferring messages with text and attachments (images, sound, video clips, etc. , ) from one Internet user to another Instant Messaging n Displays words typed on a computer almost instantly, and recipients can then respond immediately in the same way Copyright © 2011 Pearson Education, Inc. Slide 3 -38

Search Engines n Identify Web pages that match queries based on one or more techniques v Keyword indexes, page ranking n Also serve as: Shopping tools v Advertising vehicles (search engine marketing) v Tool within e-commerce sites v n Outside of e-mail, most commonly used Internet activity Copyright © 2011 Pearson Education, Inc. Slide 3 -39

Intelligent Agents (Bots) n Software programs that gather and/or filter information on a specific topic and then provide a list of results v Search bot v Shopping bot v Web monitoring bot v News bot v Chatter bot Copyright © 2011 Pearson Education, Inc. Slide 3 -41

Online Forums and Chat n Online forum: v AKA message board, bulletin board, discussion board, discussion group, board or forum v Web application that enables Internet users to communicate with each other, although not in real time v Members visit online forum to check for new posts n Online chat: v Similar to IM, but for multiple users v Typically, users log into chat room Copyright © 2011 Pearson Education, Inc. Slide 3 -42

Streaming Media n Enables music, video and other large files to be sent to users in chunks so that when received and played, file comes through uninterrupted n Allows users to begin playing media files before file is fully downloaded Copyright © 2011 Pearson Education, Inc. Slide 3 -43

Cookies n Small text files deposited by Web site on user’s computer to store information about user, accessed when user next visits Web site n Can help personalize Web site experience n Can pose privacy threat Copyright © 2011 Pearson Education, Inc. Slide 3 -44

Web 2. 0 Features and Services n Online Social Networks v Services that support communication among networks of friends, peers n Blogs v Personal Web page of chronological entries n Really Simple Syndication (RSS) v Program that allows users to have digital content automatically sent to their computers over the Internet Copyright © 2011 Pearson Education, Inc. Slide 3 -45

Web 2. 0 Features and Services n Podcasting v Audio presentation stored as an audio file and available for download from Web n Wikis v Allows user to easily add and edit content on Web page n Music and video services v Online video viewing v Digital video on demand Copyright © 2011 Pearson Education, Inc. Slide 3 -46

Web 2. 0 Features and Services n Internet telephony (VOIP) v Uses Voice Over Internet Protocol (VOIP) and Internet’s packet-switched network to transmit voice and other forms of audio communication over the Internet n Internet television (IPTV) n Telepresence and video conferencing Copyright © 2011 Pearson Education, Inc. Slide 3 -47

Web 2. 0 Features and Services n Online software and Web services v. Web apps, widgets and gadgets v. Digital software libraries, ASPs, distributed storage n M-commerce applications v. Beginning to take off Copyright © 2011 Pearson Education, Inc. Slide 3 -48

Insight on Technology Apps for Everything: The App Ecosystem Class Discussion n What are apps and why are they so popular? n Do you use any apps regularly? Which ones, and what are their functions? n What are the benefits of apps? The weaknesses? n Are there any benefits/disadvantages to the proprietary nature of the Apple platform? Copyright © 2011 Pearson Education, Inc. Slide 3 -49

All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without the prior written permission of the publisher. Printed in the United States of America. Copyright © 2011 Pearson Education, Inc. Publishing as Prentice Hall Copyright © 2011 Pearson Education, Inc.