1 / 24

Web Design and Development for E-Business

Web Design and Development for E-Business. Jensen J. Zhao. Introducing Web-Based Client/Server Applications. Chapter 8. Chapter 8 Objectives. Evolution of Client/Server Architecture Web-Based Client/Server Applications Essentials of ASP Programming and Editing Selection of ASP Tools.

sven
Télécharger la présentation

Web Design and Development for E-Business

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Web Design and Developmentfor E-Business Jensen J. Zhao

  2. Introducing Web-Based Client/Server Applications Chapter 8

  3. Chapter 8 Objectives • Evolution of Client/Server Architecture • Web-Based Client/Server Applications • Essentials of ASP Programming and Editing • Selection of ASP Tools

  4. Client/Server Architecture • Two components • Client: client computers and their software • Server: includes both hardware and software Client machines send requests to server Server processes request Server returns results to client

  5. One-Tiered Architecture • Server mainframe or minicomputer • Dumb terminals • No internal processing power • No storage capacity • All processing, calculation, storage done on mainframe • Disadvantages • Single centralized processor • Lacks flexibility and scalability

  6. Two-Tiered Architecture • Server mainframe or minicomputer • Personal computers • Processing tasks divided • Applications run on PCs • Data stored on mainframes • Disadvantages: • Complex applications are large • Client PCs become “fat”

  7. Three-Tiered Architecture • Server mainframe or minicomputer • Personal computers • Application server • Middleware • Provides applications • Acts as transaction monitor • Stores data • Advantages: • “Thin” client

  8. Web-Based Client/Server • Advantages over LANs and WANs: • No geographic boundaries • Accessible wherever Internet connection available

  9. Web-Based Architecture

  10. Browser Presentation Layer • Human-to-computer interface • Possible elements: • Home page with welcome message • Product pages with “buy” buttons • “Buy” buttons linked to product page • Order form • Shipping information

  11. Application Server Layer • Middle layer • Web server takes requests from client browser • Forwards requests to the database • Server collects responses from database • Passes responses to client browsers • Building an application server layer: • Install a Web server • Connect the server to the Internet • Create a virtual directory for the Web server • Write a Web client/server database application with HTML and DHTML

  12. Database Layer • Stores and retrieves data • SQL requests received from Web server • Database app stores data, processes results • Sends results to server • Server forwards results to client browsers • Building a database layer: • Develop database app on the server computer • Create DSNs for the user and system

  13. Impact of Applications • School sites • Registration • Check schedules, grades, exams • Business-to-business (B2B) • Supply chain management • Business-to-consumer (B2C) • Online retailing like Amazon.com • Consumer-to-consumer (C2C) • Online auctions like eBay

  14. Development of Applications • Browser presentation layer • HTML • Application server layer • ASP, Visual Basic, VBScript, Java, JavaScript, Coldfusion, CGI, Perl • Database layer • Web-enabled database software • Access, SQL Server, Oracle • DSNs • Enable database access through application layer

  15. ASP Programming • Secure, server-side scripting • Viewable with any browser • Open development environment combines • Scripting • Pre-built objects • ASP delimiters <% . . .%> • Five primary ASP objects

  16. Request Object • Purpose: to get information from the user • Submits info to Web server • Basic data collection functions: • Form • QueryString • ServerVariables • Cookies

  17. Response Object • Purpose: to send information to the user • Delivers to client browser • Basic functions: • Changing cookies • Controlling properties of objects • Controlling actions of objects

  18. Server Object • Purpose: to control connections to external components • Used in nearly every ASP file • Supports only one property • ScriptTimeout • Determines maximum time an ASP file can take to complete an execution

  19. Session Object • Purpose: to store information about and change settings for the user’s current Web-server session • Automatically created when new visitor arrives at application page • Enables application to keep track of visitors

  20. Application Object • Purpose: to share application-level information and control settings for the lifetime of the application • Created at Web server when you create a virtual directory for the application

  21. ActiveX Data Objects • Interface with other relational databases • Use ODBC • Three objects: • Connection • Recordset • Command

  22. Selection of Tools • Minimum requirements to program, test and edit ASP: • Web browser • Web server • Web-enabled database software • Minimum requirements to program and edit ASP: • Netscape Composer • Windows Notepad

  23. Chapter 8 Summary • Client/Server Architecture • Web-Based Client/Server Architecture • Browser Presentation Layer • Application Server Layer • Database Layer • Impact of Applications • Development of Applications • Essentials of ASP Programming • Selection of Tools

  24. Introducing Web-Based Client/Server Applications The End

More Related