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THE INTERNET & E-COMMERCE IS 340 BY CHANDRA S. AMARAVADI 1 PRESENTATION OVERVIEW Background Architecture Protocols TCP/IP HTTP and HTML Browser & web search Security Electronic commerce 2 BACKGROUND Started as a research network Released into public domain in 1993 Web technology (web pages) in 1992 Publicly owned (Lucent, Pac Bell etc.) Costs borne by ISPs & industry 200 million users on the web world wide 3 INTERNET ARCHITECTURE 4 BASIC ARCH. CONCEPTS Packetizing IP addresses Bridges and routers Root servers Hi-speed back bone 5 PACKETIZING DATA Document …. Packet 1 Packet 2 6 IP ADDRESSING NODE NODE NODE (143.43.78.84) NODE (153.54.56.82) 7 BRIDGES AND ROUTERS 143.43.78.84 Network Bridge Gateway Network 143.43.78.84 Network Network Router 143.43.78.84 Network 153.54.56.82 8 ROOT SERVER (DNS) NODE ROOT SERVER ROOT SERVER NODE A root/DNS server provides address information to gateways 9 BASIC ARCH. CONCEPTS.. HIGH SPEED BACKBONE NAP Regional hub Regional network 10 ARCHITECTURE The Internet is a network of networks 50,000 world wide 29,000 in USA 16 million hosts WWW - A network of webservers (content in HTML) -- 3.6 million web sites 11 ARCHITECTURE Millions of hosts connected Physical connection is a bridge (hub) Each “host” has a unique IP address Hosts can be PCs, Web servers, Mainframes Use uniform protocols (TCP/IP) Data is sent as packets Addressed by hosts Routed by routers 12 ARCHITECTURE Bridges, routers, gateways maintain directories, move data Internet 13 ARCHITECTURE WEB SITES Browsers (terminals that access the web site -called clients) A web server (a special computer or minicomputer that will host the site) Server software (to run TCP/IP protocols) Web content i.e. the web page Firewall (mechanisms (HW/SW) for security) 14 SERVER ARCHITECTURE (FYI) FTP DNS CLIENT ACCESS AUTHORING TOOLS NETWORK OPERATING SYSTEM SERVER BOX INTERNET INTERFACE/FIREWALL INTERNET SERVICE PROVIDER 15 ISP ARCHITECTURE Backbone VBNS -- Very High Speed Backbone Network Access Pts. PacBell Internet Access Sprint Local Access Local Provider End Users Home Users MCI Verizon Local Local Provider Provider Small Bus. Lucent Lucent Ameritech AOL Local Provider Large Bus. UUnet PSI Local Provider Govt. 16 INTERNET PROTOCOLS 17 A HIERARCHY OF PROTOCOLS Application Host level Gateway level Network level + + + + FTP, Telnet, HTTP TCP IP FDDI, Ethernet, Token ring, CSMA/CD ,X.25, ISDN 18 A HIERARCHY OF PROTOCOLS (CSMA/CD) (FDDI) BROWSER (HTTP) (Ethernet) HOST HOST (TCP/IP) (TCP/IP) WEB SERVER (HTTP) 19 TCP/IP PROTOCOL Protocol for reliable data transfer A collection of 100 protocols Hardware independent Data is packetized Rules for formatting messages establishing sessions governing transmissions Application Host Gateway Network access 20 Source P ort D estination P ort Sequence # Acknow ledgem ent # P arity O ptions D ata Port#, seq#, parity,... message Document …. Packet 2 Packet 1 HTTP TCP 21 INTERNET PROTOCOL (IP) A protocol for assigning & resolving IP addresses Unique address. Assigned by IETF/ICANN. In the form of a domain name (ibm.com). Email addresses based on this ([email protected]) Translated to “dotted quad”:203.48.54.28. What are some common domain extensions? 22 A HIERARCHY OF PROTOCOLS (CSMA/CD) (FDDI) BROWSER (HTTP) (Ethernet) HOST HOST (TCP/IP) (TCP/IP) WEB SERVER (HTTP) 23 HTTP – Hypertext Transport Protocol A protocol for formatting and transferring multimedia objects, text, etc. “Stateless protocol” Data is sent as plain character text Rules specify both request and response format 24 HTTP – Hypertext Transport Protocol (FYI) REQUEST GET ACCEPT USER AGENT CONNECTION Myfile.htm http/1.0 image, bitmap, JPG Netscape 9.0 Keep alive 25 HTTP – Hypertext Transport Protocol (FYI) RESPONSE Http/2.0: OK Server: Netscape Last modified: 3/9/08 Content length: 10 KB 26 HYPERTEXT MARKUP LANGUAGE 27 HTML – HYPERTEXT MARKUP LANGUAGE… A tagging language based on SGML Text appearance and structure is governed by embedded commands or tags. Example bold, paragraph etc. There’s a start tag and end tag (e.g. <B>Text to be bolded </B>) 28 HTML – HYPERTEXT MARKUP LANGUAGE THREE MAJOR TYPES OF TAGS Structuring tags -- e.g. heading, body, frame etc. Formatting tags -- e.g. bold, italic, font etc. Hyperlink tags -- e.g. image, sound etc. 29 STRUCTURING TAGS <HTML> . . . To begin & end HTML . </HTML> 30 STRUCTURING Heading Window title <Head> <title> Main page of spectrum </title> </Head> Web page heading <H1> …………………………… </H1> <H2> ………………………….. </H2> 31 STRUCTURING Body <Body> . . Main part of web page </Body> <Body Bgcolor= “color” text=“color” link=“color” vlink=“color” alink= “color”> 32 FORMATTING Font <font size= “number” face= “font name”> color= “color” Size = “+1” “+2” 33 FORMATTING Paragraph <P> ……………. </P> Alignment <P align = “Left”> _______________ _______________ _______________ </P> Aligns left Bold Italic Line Breaks <B> …………. </B> <I>…………... </I> <BR> 34 HYPERLINKS URL: Uniform Resource Locator, address of a resource on the internet; resource could be?? <a href = “URL of page” > text or image for user to click on </a> e.g. <a href = http://www.cnn.com> CNN </a> <a href = “http://www.faculty.wiu.edu/C-Amaravadi/”> Course web sites </a> 35 IMAGES & HYPERLINKS Image <img src = “URL of image” height = “number” width = “number”> height width For text wrap add ALIGN = “Left” 36 HTML – HYPERTEXT MARKUP LANGUAGE <HTML> <HEAD> <!-- Title and main heading --> <TITLE> Main Menu </TITLE> </HEAD> <!-- Begin body--> <BODY BGCOLOR = “#FFFF6B” TEXT = “#A50063> <P> <IMG SRC=“logo.jpg” height = 100 width = 600> </P> </HTML> 37 HTML – HYPERTEXT MARKUP LANGUAGE <B> ABOUT US </B> <BR> Founded in 2006, our corporate mission....... <SPACER TYPE = HORIZONTAL SIZE = 20> Varyti Broadcasts -- TV Program Division .................... </BODY> </HTML> 38 BROWERS & EXTENSIONS 39 BROWSERS Software to view web pages e.g. Internet Explorer, Firefox. Functions: Connection & data transfer request connection by sending HTTP request Respond to HTTP receive response and displays information Display web pages Create web pages 40 WEB TECHNOLOGIES Plug-ins Java JSP (Java Server Pages) Servlets Programs that work with browser, e.g. audio & video players. programming language to build web applications. used to create dynamic html pages. compiled JSP to respond to http requests. 41 WEB SEARCH TOOLS/ENGINES Enable web search (look for keywords) Store keywords & web locations Use indexing Google Yahoo Answers.com 42 INTERNET SECURITY 43 INTERNET SECURITY Firewall -- a system designed to protect a web-site from unauthorized access Principles are: Packet filtering protected host (bastion host) dedicated routers/switches monitoring and logging of users Internet 44 E-COMMERCE 45 WHAT IS E-COMMERCE? • Business conducted on the web • Buyers and sellers interact electronically Products/Services BUYER Online Transactions Payments What is M-commerce? SELLER Cust to business (B2C) ◦ ordering products, books, sw, music, consumer products ◦ services, banking & finance, stock trades Business to Business (B2B) ◦ supply of raw materials Intra-Org ◦ inventory ordering & charge out, etc. ◦ helpdesk, etc. Retail e.g. books, toys etc. Premium content e.g. CNN & financial companies Auctions e.g. cars, steel, power Gateways, search engines DISCUSSION What are the pros & cons of e-commerce? (to customers and to businesses) E-COMMERCE MODEL Product Search Comparison shopping Placement of order Payment information Payment authorization Receive merchandise Service and support E-COMMERCE ARCHITECTURE Incoming Internet request Web Server layer Web Server Middle-tier layer E Commerce Sever Database Backend layer ERP System Mainframe ECOMMERCE ISSUES Volatility of information -- updates Ensuring adequate security Ethical usage of customer information Advertising Legal issues – sales, contracts etc. That’s All Folks! 53