1. Mainframe (Host) - Communications - User Interface - Business Logic - DBMS - Operating System - Storage (DB Files) Terminal (Display/Keyboard) Terminal (Display/Keyboard) Terminal (Display/Keyboard) Mainframe Architecture

2. Source: http://www.cs.ncl.ac.uk/events/anniversaries/40th/webbook/photos/index.html

3. Personal Computer or Workstation - User Interface - Business Logic - DBMS - Operating System - Storage (DB Files) Stand-Alone PC Architecture

4. File Server - Communications - Operating System - Storage (DB Files) Client - User Interface - Business Logic - DBMS - Communications - Operating System File Sharing Architecture Client - User Interface - Business Logic - DBMS - Communications - Operating System Local area network

5. Database Server - Communications - DBMS - Operating System - Storage (DB Files) Client - User Interface - Business Logic - Communications - Operating System “Classic” Client/Server Architecture Local area or wide area network Client - User Interface - Business Logic - Communications - Operating System

6. Client PC - User Interface - Business Logic - DB Driver - Communications - Operating System Database Server - Storage (DB Files) - Operating System - DBMS - DB Listener - Communications Client/Server Interaction SQL Request Server Response

7. Database Server - Communications - DBMS - Operating System - Storage (DB Files) Client - User Interface - Communications - Operating System Three Tier Client/Server Architecture Local area or wide area network Client - User Interface - Communications - Operating System Applications Server - Business Logic - Operating System - DB Driver - Communications Variation 1: Application Server

8. Database Server - Communications - DBMS - Operating System - Storage (DB Files) Client - User Interface - Communications - Operating System Three Tier Client/Server Architecture Local area or wide area network Client PC - User Interface - Communications - Operating System Transaction Processing Server - Transaction Processor - Operating System - DB Driver - Communications Variation 2: Transaction Processing Server

9. Database Server (Node) - Application(s) - Communications - DBMS - Operating System - Storage (DB Files) Distributed Database Architecture Local area or wide area network Database Server (Node) - Application(s) - Communications - DBMS - Operating System - Storage (DB Files) Database Server (Node) - Application(s) - Communications - DBMS - Operating System - Storage (DB Files)

10. Open DataBase Connectivity (ODBC) Application ODBC API Oracle ODBC Driver Sybase ODBC Driver Oracle RDBMS Sybase RDBMS ODBC Oracle DB Driver Sybase DB Driver

11. Database Server - Communications - DBMS - Operating System - Storage (DB Files) Client User Interface: Web Browser HTML Forms JavaScript Communications: TCP/IP Operating System Web Access to DBMS Local area or wide area network Web Server - HTTP Server - Web Application - Internet Comm: TCP/IP - DB Comm.: DB Driver - Operating System 1) Client PC running web browser submits a query via an HTML form to the web server 2) Web server / application uses CGI to unpack query and pass it to the DB Driver 3) Web app. uses DB Driver to package the query and send it to the DB Server 4) Query is processed and results returned to web app. 5) Web app. formats results as HTML and web server send back to web browser