Chapter 9

Comparing Web Technologies

Agenda

• Browser

• Hypertext Markup Language (HTML)

• Common Gateway Interface

• Web Application Server

• Plug-in

Browser

• Selection Criteria

• Popular Browser

• Next generation

Selection Criteria

• OS platform– Unix– Windows– Lynx

• Standards– World Wide Web Consortium (W3C)– Backward-compatible– Forward-compatible

Selection Criteria

• Functions– Frames– Forms– Tables– Fonts– Cascade style sheet (CSS)– JavaScript– Java

Selection Criteria

• Functions– Plug-ins– News– Mail– HTML editor

• Reliability

• Cost

Selection Criteria

• Support– Vendor– Third party

• Hardware requirement– Server side– Client side

• Speed/performance

Selection Criteria

• Types– Text-based– Multimedia-based– Online– Offline (Offline Explorer)

• Standard compliance

• Can you think any other selection criteria for browser?

Popular Browser

• Netscape Communicator

• Internet Explorer

• Opera

• Lynx

• Amaya

• Arachne

• HotJava

Next Generation

• Desired features– Integrated Internet service– Open source code for quality and portability– Real-time communication for chat– Small and modular programs– Speed– Standards Compliance– Anything else?

Next Generation

• Reality– Incompatible/proprietary feature– Complexity/more memory requirement– Unreliable/more bug/more insecure

What do you think about the reality?

Agenda

• Browser

• Hypertext Markup Language (HTML)

• Common Gateway Interface

• Web Application Server

• Plug-in

Hypertext Markup Language

• HTML 4.0

• Dynamic HTML

• Extensible markup language

Agenda

• Browser

• Hypertext Markup Language (HTML)

• Common Gateway Interface

• Web Application Server

• Plug-in

Common Gateway Interface

• General concepts

• Languages

• Language selection criteria

General Concept

• Common gateway interface (CGI) enables interaction between a web server and a browser using the hypertext transfer protocol (HTTP)

• CGI handles information requests and return the appropriate document or generate a dynamic document

• CGI is a gateway between database and web browser

Languages

• C• C++• Java• JavaScript• Jscript• ECMAScript• Perl• Python• VisualBasic Script

Language Selection Criteria

• Hardware-independent• Browser-independent• Fast prototyping• Easy to use and read• Efficient and complete• Object-oriented• Portable• Multi-platform environment• Event handling and client-side execution• Create and read cookies

Agenda

• Browser

• Hypertext Markup Language (HTML)

• Common Gateway Interface

• Web Application Server

• Plug-in

Web Application Server

• General Concepts

• Selection Criteria

• Products

General Concepts

• Three-tier architecture– Client– Database server– Web application server

• Functions of web application server– Transaction management– Clustering and load balancing

Selection Criteria

• Easy to use

• Functions– File, proxy, redirect and virtual hosting

• Interaction with heterogeneous databases

• Availability

• Security

• Scalability

Selection Criteria

• Performance

• Transaction Integrity

• Speed

• Quality of service

• Rapid application development

• Platform-independent

Selection Criteria

• Manageability

• Portability

• Integration with legacy systems

Can you think any other selection criteria for web application server?

Products

• Avenida Web Server

• Bea WebLogic Enterprise

• Cold Fusion

• Enterprise Application Server

• eXcelon

• Inprise Application Server

• Lotus Domino Application Server

Products

• Netwcape Application Server

• SilverStream

• WebObjects

• WebSphere Application Server

• Sope

Agenda

• Browser

• Hypertext Markup Language (HTML)

• Common Gateway Interface

• Web Application Server

• Plug-in

Plug-in

• Purpose

• Products

Purpose

• Interact with browser, web pages, local and Internet resources

• Native application for a certain processor, hardware and operating system

Products

• Adobe Acrobat Reader– Acrobat portable document format (PDF)– Distribute online brochure and technical

documentation via Internet

• Apple Quicktime– Maximum exposure and viewing multimedia

CD-ROM on the web

Products

• Platinum Cosmoplayer– Display documents in the virtual reality markup

language (VRML)– 3D world

• Macromedia Shockwave– Standard plug-in for multimedia on Internet

Do you have any experience with these products?

Points to Remember

• Browser

• Hypertext Markup Language (HTML)

• Common Gateway Interface

• Web Application Server

• Plug-in