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Chapters 14 & 15 Internet Databases E-Commerce Bringing new products, services, or ideas to market, supporting and enhancing business operations Mainly identified with the use of the Internet as a medium to transact business and add value to an organization. Changed Business Environment Benefits of E-Commerce Convenience Quick and Convenient Comparison Shopping Reduced Cost / Increased Competition 24 / 7 / 365 operations Global Access Lower Entry Barriers Increased Customer Market Knowledge Disadvantages of E-Commerce Hidden Costs – Hardware – Software Technology is not perfect Thin profit margins (must be competitive) Security Loss of Privacy Low Levels of Customer Service Legal Issues Major E-Commerce Styles Business to Business (B2B) Business to Consumer (B2C) – Consumer to Business – Consumer to Consumer – Government to Consumer – Government to Business IntraBusiness (using Intranet) E-Commerce Architecture 3 Layered Organization of Services that interact, using a common set of protocols. The Internet is the main transport medium. Basic Internet Services Business Enabling Services E-Commerce Business Services Basic Internet Services Web Browser HTML FTP HTTP TCP/IP Web Server E-Mail Business Enabling Services Security Personalization Database Integration Usability Testing Web Site Monitoring and Analysis Transaction Processing Search Messaging Wireless Device Support E-Commerce Business Services Inventory Ordering Tracking Product Support Customer Service Shipping Etc. Security Protect transaction data from unauthorized modifications during Internet travel – Transaction Security – Secure Socket Layer – S-HTTP Authentication - Warrantee identity of transaction participants (Buyers and Sellers) Protect Resources (data and computer) Customer’s personal data Privacy Issues Property against Criminal Activity – Digital Certificated – Encryption Private Key Public Key Resource Security – Protect against virus, hackers, DOS attacks Database Design for E-Commerce Don’t reinvent the wheel No need for ‘new’ design techniques Scope – Facilitate sales of products and services – Show products and services – Conduct basic sales transactions – Customer Service – Product Returns Web Customer Profiling Basic Business Rules Sell Products Product and Customer Tables Customer may place multiple orders – 1:M Relationship Order contains Multiple Lines – 1:M Relationship Order Lines refer to one Product – 1:M Relationship XML – Extensible Markup Language Meta-Language Represents and Manipulates data elements Facilitates Exchange of structured documents over the web – World Wide Web Consortium (W3C) published standard definition in 1998 Allow definition of meta-tags to describe data elements Case Sensitive Not A Replacement for HTML XML – Document Type Definition Files with .dtd extension to describe XML elements Provides composition of database’s logical model Defines syntax rules for each XML documents Defines Valid tags XML Schema Advances data definition language used to describe structure of XML documents Closely maps database terminology and features Checks for database types Validates data for out-of-range values XML Schema Definition (XSD) files use syntax like SML document Web Databases Stateless Environment – The web is a stateless system. Data processing requires additional software – Java – Java Script – VB Script Web Database Connectivity Allows rapid response to competitive pressures – New Services – New Products Enhanced Customer Support Fast Effective Information Dissemination Characteristics / Benefits of Internet Technology Hardware / Software Independence – Cost Savings – Uses Existing Equipment – Platform Independency Common Simple User Interface – Reduced Training and Support Location Independence – Global Access – Reduced Costs for Dedicated Connections Rapid Development at Manageable Cost – Development Tools (Plug and Play) – Low Entry Costs (Often Free Web Servers) – Available Software and Access Tools Web Server Interfaces CGI – Common Gateway Interfaces – Uses Script files to connect to database – Perl, C++, VB API – Application Programming Interface – – – – Newer More Efficient Uses DLL’s Memory Resident Netscape API Internet Server API (Microsoft) Cold Fusion – Web Application Server Web Server Application Middleware application Expands functionality of Web servers by connecting them to wide range of services – Databases – Directory Systems – Search Engines Provides a Consistent Run-Time Environment for Web-Applications Allows Client to Interact with Databases and Present Database-Driven Data in a Web Page Server Side Extension Part of Web Server Application Interacts directly with web server Handles specific requests Middleware Connectivity to Databases Native SQL ODBC (most common) OLC DB – Object Linking and Embedding Database Interface – Windows Web Browser – Client Machine End User Web Interface Interprets HTML Client-Side Extensions – Plug Ins – Java / Java Script – Active X and VB Script Special Considerations for Internet Databases Involved more than just database-enabled applications Data Types – Integrate from Multiple Sources – How to store and extract data – Overhead – Browser Support Special Considerations for Internet Databases Data Security – – – – Web Server Level RMDBS Vendor Web to Database Middleware Must Support E-Commerce Transaction Management (stateless env.) Client Side Data Validation Cannot Use Multiple Table Data Entry – Requires Denormalization of Tables Other Operational and Management Challenges