Web-based Software Development - An introduction

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Web-based Software Development- An introduction
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The Client/Server Model

• ?  Process to process communication (PPC)
• The underlying platform of the client/server
  programming.

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The Client/Server Model
?  Two Tier (Traditional) Client/Server Model
Exercise Name a commonly used client/server
technique.

• Sockets programming

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The Client/Server Model
?  Three Tier Client/Database/Server Model
? ?
APIs JDBC ADO
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The Client/Server Model
?  Two Tier Web Based Model
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Three Tier Web Based Model
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Multi-Tier Web Based Model
Various configurations?

• Multiple Databases

• Distributed Databases

• Multiple application instances

• Web server farm

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Sample Web Based Applications

• dynamic web pages interactive i/o
• multimedia presentations
• Web based multi-player games

• access to remote databases
• connectivity to legacy computer systems
• front end of a transaction application

• intranet applications

• scientific simulation and visualization

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Sample Web Based Applications- scientific
simulation and visualization
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Representative Web technology
- Client Side Development

• Interpreted or executed by the client (that is,
  the Web browser).
• Note Web pages are originally stored on the Web
  server.

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Representative Web technology
- Client Side Development

• ?  Issues with client side scripting
• Inconsistent support across the Web browsers

• Source exposed to the viewer

• Security

• Awkward connectivity to back-end (e.g., ODBC)

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Representative Web technology
- Server Side Development

• Interpreted or executed by the server side
  applications.
• The result is then sent back to the Web browser.

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Representative Web technology
?  Server Side Technologies

• Common Gateway Interface (CGI)
• Active Server Pages (ASP)
• Java Servlets
• Java Server Pages (JSP)
• Distributed Components-Based Technology (
  CORBA, DCOM, EJB, RMI, )

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Representative Web technology
?  Database Connections

• JDBC Java Database Connectivity
• ODBC Open Database Connectivity
• OLE-DB
• ADO ActiveX Data Objects

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Representative Web technology
Components Programming Tools - languages, technologies and APIs
Web Browsers Internet Explorer, Netscape Navigator
Web Servers   Apache, IIS,
Applications (Servers) Oracle Application Server, WebSphere Advanced Server, WebLogic, Netscape Enterprise Server,
Database Servers Oracle Database Server, MS SQL Server, IBM DB2, SyBase, Informix,
Java Virtual Machines (JVMs), plug-ins, activeX components, ...
Client-side programming HTML, JAVA Applets, Java Script, VB Script, VRML, XML,
Server-side programming Java Servlets, Java Server Pages, Active Server Pages, CGI, Java Script, VB Script, ...
ODBC, JDBC, ADO, SQL Net, SQLJ, ...