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In this chapter, the learning objectives are: Define the origin and evolution of the internet, identify the key technology concepts behind the internet describe the role of internet protocols and utility programs explain the current structure of internet, understand the limitations of todays internet describe the potential capabilities of internet ii understand how the world wide web works describe how internet and web features and services support e-commerce.
CSC 330 E-Commerce Teacher Ahmed Mumtaz Mustehsan GM-IT CIIT Islamabad • • Virtual Campus, CIIT COMSATS Institute of Information Technology • T1-Lecture-3 The Internet and The Web Chapter-2 Part-I T1-Lecture-3 For Lecture Material/Slides Thanks to: Copyright © 2010 Pearson Education, Inc Objectives Define the origin and evolution of the Internet Identify the key technology concepts behind the internet Describe the role of Internet protocols and utility programs Explain the current structure of Internet Understand the limitations of todays internet Describe the potential capabilities of Internet II Understand how the world wide web works Describe how internet and web features and services support e-commerce T1-Lecture-3 Ahmed Mumtaz Mustehsan Copyright © 2010 Pearson Education, Inc 1-3 The Internet: Technology Background Internet Interconnected network of thousands of networks and millions of computers Links businesses, educational institutions, government agencies, and individuals World Wide Web (Web) One of the Internet’s most popular services Provides access to around billions, possibly trillions, of Web pages T1-Lecture-3 Ahmed Mumtaz Mustehsan Copyright © 2010 Pearson Education, Inc 1-4 The Evolution of the Internet 1961 - Present Innovation Phase, 1964 -1974 Institutionalization Commercialization T1-Lecture-3 Phase, 1975 -1994 Phase,1995 - present Ahmed Mumtaz Mustehsan Copyright © 2010 Pearson Education, Inc 1-5 The Evolution of the Internet 1964 - 1974 Innovation Phase: (1964 -1974) The basic building blocks were introduced such as; packet-switching hardware, client/server computing, and a communications protocol called TCP/IP The original purpose of the Internet, was to link large mainframe computers on different university/college campuses This kind of one-to-one communication between campuses was previously possible only through the telephone system or postal mail T1-Lecture-3 Ahmed Mumtaz Mustehsan Copyright © 2010 Pearson Education, Inc 1-6 The Evolution of the Internet 1975 -1994 Institutionalization Phase: (1975 -1994) Large institutions such as the US Department of Defense (DoD) and the National Science Foundation (NSF) provided funding to legitimate for the fledging invention called the Internet DoD contributed $1 million to further develop the network into a robust military communications system so that it could withstand during nuclear war In 1986, the NSF assumed responsibility for the development of a civilian Internet (NSFNET) and began a ten-year-long $200 million expansion program T1-Lecture-3 Ahmed Mumtaz Mustehsan Copyright © 2010 Pearson Education, Inc 1-7 The Evolution of the Internet (1995Present) Commercialization Phase: (1995 – present) Government agencies encouraged private corporations to take over and expand both the Internet backbone and local services to ordinary citizens who were not students By 2000, the Internet’s use had expanded well beyond military installations and research universities and came into the public domain T1-Lecture-3 Ahmed Mumtaz Mustehsan Copyright © 2010 Pearson Education, Inc 1-8 An instance of internet - active nodes Source: http://www.glossar.de/glossar/1frame.htm? T1-Lecture-3 Ahmed Mumtaz Mustehsan Copyright © 2010 Pearson Education, Inc 1-9 The Internet: Key Technology Concepts Network as Defined by NSF: Uses IP addressing Supports TCP/IP Provides services to users, in manner similar to telephone system Three important concepts: Packet switching TCP/IP communications protocol Client/server computing T1-Lecture-3 Ahmed Mumtaz Mustehsan Copyright © 2010 Pearson Education, Inc 110 The Internet Today Internet growth has boomed without disruption because it is based on some powerful applications using the following architecture: 1.Client/server computing model 2.Pear to Pear P2P Model 3.Cloud Computing Hourglass, layered architecture ◦ Network Technology Substrate ◦ Transport Services and Representation Standards ◦ Middleware Services ◦ Applications T1-Lecture-3 Ahmed Mumtaz Mustehsan Copyright © 2010 Pearson Education, Inc 130 Client/Server Computing Powerful personal computers (clients) connected in network with one or more servers Servers perform common functions for the clients, such as Storing files, software applications, etc T1-Lecture-3 Ahmed Mumtaz Mustehsan Copyright © 2010 Pearson Education, Inc 131 Client Server T1-Lecture-3 Ahmed Mumtaz Mustehsan Copyright © 2010 Pearson Education, Inc 132 The New Client: The Emerging Mobile Platform Within a few years, primary Internet access will be through: Netbooks ◦ Designed to connect to wireless Internet ◦ Under lbs, solid state memory, 8” displays ◦ $200–400 Smartphones ◦ Disruptive technology: Processors, operating systems T1-Lecture-3 Ahmed Mumtaz Mustehsan Copyright © 2010 Pearson Education, Inc 133 Cloud Computing Obtain Software and hardware as Service Firms and individuals obtain computing power (hardware) and software over Internet ◦ E.g., Google Apps Fastest growing form of computing Radically reduces costs of: ◦ Building and operating Web sites ◦ Infrastructure, IT support ◦ Hardware, software T1-Lecture-3 Ahmed Mumtaz Mustehsan Copyright © 2010 Pearson Education, Inc 134 Cloud Computing T1-Lecture-3 Ahmed Mumtaz Mustehsan Copyright © 2010 Pearson Education, Inc 135 Cloud Computing Model T1-Lecture-3 Ahmed Mumtaz Mustehsan Copyright © 2010 Pearson Education, Inc 136 Other Internet Protocols and Utility Programs Internet protocols HTTP E-mail: SMTP, POP3, IMAP, FTP, Telnet, SSL Utility programs Ping Tracert Pathping NSlookup T1-Lecture-3 Ahmed Mumtaz Mustehsan Copyright © 2010 Pearson Education, Inc Slid e 3 37 Other Internet Protocols and Utility Programs HyperText Transfer Protocol (HTTP) is the Internet protocol used to transfer Web pages HTTP was developed by the World Wide Web Consortium (W3C) HTTP runs in the Application Layer of the TCP/IP model An HTTP session begins by the client’s browser requesting a resource, such as a Web page, from a remote Internet server When the server responds by sending the page requested, the HTTP session for that object ends Web pages may have many objects such as graphics, sound or video files, frames, so each object must be requested by a separate HTTP message The most common HTTP request message is Get, used to request a resource T1-Lecture-3 Ahmed Mumtaz Mustehsan Copyright © 2010 Pearson Education, Inc 138 Other Internet Protocols and Utility Programs Simple Mail Transfer Protocol (SMTP) Is an Internet protocol used to send e-mail to a server SMTP is a relatively simple, text-based protocol that was developed in the early 1980s SMTP handles only the sending of e-mail T1-Lecture-3 Ahmed Mumtaz Mustehsan Copyright © 2010 Pearson Education, Inc 139 Other Internet Protocols and Utility Programs To retrieve e-mail from a server, The client computer uses Post Office Protocol (POP3) A protocol used by the client to retrieve mail from an Internet server and then delete the messages on the server, or retain them on the server Internet Message Access Protocol (IMAP) IMAP is a more current e-mail protocol supported by all browsers and most servers and ISPs IMAP allows users to search, organize, and filter their mail prior to downloading it from the server T1-Lecture-3 Ahmed Mumtaz Mustehsan Copyright © 2010 Pearson Education, Inc 140 Other Internet Protocols and Utility Programs File Transfer Protocol (FTP) One of the original Internet services Part of the TCP/IP protocol that permits users to transfer files from the server to their client computer, 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 megabyte, which some e-mail servers will not accept Telnet A terminal emulation program that runs in TCP/IP The term Telnet also refers to the Telnet program, which provides the client part of the protocol and enables the client to emulate a mainframe computer terminal T1-Lecture-3 Ahmed Mumtaz Mustehsan Copyright © 2010 Pearson Education, Inc 141 Other Internet Protocols and Utility Programs Secure Sockets Layer (SSL) 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 T1-Lecture-3 Ahmed Mumtaz Mustehsan Copyright © 2010 Pearson Education, Inc 142 P2P Class Discussion How does P2P networking differ from client/server networking? Why is P2P networking a potential money-saver for corporations and other organizations? What are some illegal uses of P2P networking? What are some legal uses of P2P networking? What other alternatives are there for streaming large video files? T1-Lecture-3 Ahmed Mumtaz Mustehsan Copyright © 2010 Pearson Education, Inc Slid e 3 43 End The Internet and The Web Chapter-2; Part-I T1-Lecture-3 For Lecture Material/Slides Thanks to: Copyright © 2010 Pearson Education, Inc .. .The Internet and The Web Chapter- 2 Part-I T1 -Lecture- 3 For Lecture Material/Slides Thanks to: Copyright © 2010 Pearson Education, Inc Objectives Define the origin and evolution of the Internet. .. todays internet Describe the potential capabilities of Internet II Understand how the world wide web works Describe how internet and web features and services support e-commerce T1 -Lecture- 3... large video files? T1 -Lecture- 3 Ahmed Mumtaz Mustehsan Copyright © 2010 Pearson Education, Inc Slid e 3 43 End The Internet and The Web Chapter- 2; Part-I T1 -Lecture- 3 For Lecture Material/Slides