Ahmed Mumtaz Mustehsan 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

The Internet: Technology Background 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

The Evolution of the Internet 1961 - Present Innovation Phase, 1964 -1974 Institutionalization Phase, 1975 -1994 Commercialization Phase,1995 - present T1-Lecture-3 Ahmed Mumtaz Mustehsan Copyright © 2010 Pearson Education, Inc

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

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

The Evolution of the Internet (1995- Present) 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

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

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

Packet Switching Packet Switching: Slices digital messages into packets Sends packets along different communication paths as they become available Reassembles packets once they arrive at destination Uses routers Special purpose computers that interconnect the computer networks make up the Internet and route packets. Routing algorithms ensure packets take the best available path toward their destination. Less expensive, wasteful than circuit-switching. T1-Lecture-3 Ahmed Mumtaz Mustehsan Copyright © 2010 Pearson Education, Inc

Packet Switching Packet Switching Demo http://www.pbs.org/opb/nerds2.0.1/geek_glossary/packet_switching_flash.html T1-Lecture-3 Ahmed Mumtaz Mustehsan Copyright © 2010 Pearson Education, Inc

Key Concept Related to TCP/IP Protocol A set of rules and standards for data transfer Transmission Control Protocol/Internet Protocol (TCP/IP) the core communications protocol for the Internet TCP Protocol that establishes the connections among sending and receiving Web computers and handles the assembly of packets at the point of transmission, and their reassembly at the receiving end IP protocol that provides the Internet’s addressing scheme and is responsible for the actual delivery of the packets T1-Lecture-3 Ahmed Mumtaz Mustehsan Copyright © 2010 Pearson Education, Inc

TCP/IP Internet Protocol (IP): Provides the Internet’s addressing scheme. Transmission Control Protocol (TCP): Establishes connections between sending and receiving Web computers Handles assembly of packets at point of transmission, and reassembly at receiving end Four TCP/IP Layers (hourglass model) Network Interface Layer Internet Layer Transport Layer Application Layer T1-Lecture-3 Ahmed Mumtaz Mustehsan Copyright © 2010 Pearson Education, Inc

The TCP/IP Architecture and Protocol Suite T1-Lecture-3 Ahmed Mumtaz Mustehsan Copyright © 2010 Pearson Education, Inc

Key Concept Related to TCP/IP Network Interface Layer: Responsible for placing packets on, and receiving them from, the network medium. Internet Layer Responsible for addressing, packaging, and routing messages on the Internet Transport Layer Responsible for providing communication with the application by acknowledging and sequencing the packets to and from the application T1-Lecture-3 Ahmed Mumtaz Mustehsan Copyright © 2010 Pearson Education, Inc

Key Concept Related to TCP/IP Application Layer Provides a wide variety of applications (HTTP, FTP, SMTP ) with the ability to access the services of the lower layers of TCP/IP. Internet address Internet address expressed a unique number that appears as a series numbers separated with periods, such as 64.49.254.91 carrying the address of an individual machine on the internet. T1-Lecture-3 Ahmed Mumtaz Mustehsan Copyright © 2010 Pearson Education, Inc

Internet (IP) Addresses How 500 million people will be addressed? The answer is IP addressing version 4 (IPv4) used previously and IP addressing version 6 (IPv6) a new version introduced lately to accommodate more clients. IPv4 32-bit number IPv4 can handle 4 billion. Expressed as series of four sets of separate numbers marked off by periods e.g. 201.61.186.227 or 130.111.67.244 Class B address: (130.111.67.244) Network identified by first two sets, computer identified by last set Class C address: (201.61.186.227) Network identified by first three sets, computer identified by last set T1-Lecture-3 Ahmed Mumtaz Mustehsan Copyright © 2010 Pearson Education, Inc

Internet (IP) Addresses IPv6 A newer version of the IP protocol, called IPv6, has been developed. IPv6 provides for 128-bit addresses, or about 1 quadrillion (10 to the power15) T1-Lecture-3 Ahmed Mumtaz Mustehsan Copyright © 2010 Pearson Education, Inc

Checking your IP From start menu click Run Type cmd in dialogue box Type ipconfig T1-Lecture-3 Ahmed Mumtaz Mustehsan Copyright © 2010 Pearson Education, Inc

Routing Internet Messages: TCP/IP and Packet Switching The Internet uses packet-switched networks and the TCP/IP communications protocol to send, route, and assemble messages. Messages are broken into packets, and packets from the same message can travel along different routes. T1-Lecture-3 Ahmed Mumtaz Mustehsan Copyright © 2010 Pearson Education, Inc

Domain Names, DNS, and URLs IP address expressed in natural language comsats.edu.pk  203.124.43.105 Domain Name System (DNS) Allows numeric IP addresses to be expressed in natural language Uniform Resource Locator (URL) Address used by Web browser to identify location of content on the Web e.g., http://www.azimuth-interactive.com/flash_test/potocol/server/file T1-Lecture-3 Ahmed Mumtaz Mustehsan Copyright © 2010 Pearson Education, Inc

How to Pick a Domain Name Pointer for picking domain names If you sell bricks, pick a domain name containing a word like brick Consider name length and ease of remembering the name Hyphens to force search engines to see keywords in your domain name Make sure the domain name is easy for Web users to remember and find The domain name should suggest the nature of your product or service The domain name should serve as a trademark The domain name should be free of legal conflicts T1-Lecture-3 Ahmed Mumtaz Mustehsan Copyright © 2010 Pearson Education, Inc

Some memorable Internet names Bad names Yadayada.com Doggles.com ePet.com Teacherstalk.com “anything”online.com llanfairpwllgwyngyllgog erychwyrndrobwyll- llantysiliogogogoch.co m Close to an existing name Gooogle.com Goggle.com Good names Amazon.com Ebay.com Yahoo.com Google.com Alibaba.com Hotmail.com qwerty.com T1-Lecture-3 Ahmed Mumtaz Mustehsan Copyright © 2010 Pearson Education, Inc

How to Register a Domain Name if you are interested a domain In Pakistan (.pk ) You may use : https://nexus.pk/pknic.php If you want to register an international domain .com you may try : http://www.register.com/ T1-Lecture-3 Ahmed Mumtaz Mustehsan Copyright © 2010 Pearson Education, Inc

How to Register a Domain Name in Pakistan? T1-Lecture-3 Ahmed Mumtaz Mustehsan Copyright © 2010 Pearson Education, Inc

How to Register a Domain Name in Pakistan? T1-Lecture-3 Ahmed Mumtaz Mustehsan Copyright © 2010 Pearson Education, Inc

How to Register an international Domain Name ? T1-Lecture-3 Ahmed Mumtaz Mustehsan Copyright © 2010 Pearson Education, Inc

How to Register an international Domain Name ? T1-Lecture-3 Ahmed Mumtaz Mustehsan Copyright © 2010 Pearson Education, Inc

The Internet Today Internet growth has boomed without disruption because it is based on some powerful applications using the following architecture: Client/server computing model Pear to Pear P2P Model 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

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

Client Server T1-Lecture-3 Ahmed Mumtaz Mustehsan Copyright © 2010 Pearson Education, Inc

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 2 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

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

Cloud Computing T1-Lecture-3 Ahmed Mumtaz Mustehsan Copyright © 2010 Pearson Education, Inc

Cloud Computing Model T1-Lecture-3 Ahmed Mumtaz Mustehsan Copyright © 2010 Pearson Education, Inc

Other Internet Protocols and Utility Programs 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

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

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

Other Internet Protocols and Utility Programs To retrieve e-mail from a server, The client computer uses Post Office Protocol 3 (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

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 1 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

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

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

End The Internet and The Web Chapter-2; Part-I T1-Lecture-3 For Lecture Material/Slides Thanks to: Copyright © 2010 Pearson Education, Inc