Explanation of applications used in Gmail Server Architecture

Explanation of applications used in Gmail Server Architecture 

Conclusions from the above diagram 

Every real worls project contains below three application

• Web supprtive application 
• Web application
• Data interaction application

In JAVA we develop above applications using

• HTML/Applet- to develop web supportive application
•  Servlet and JSP- to develop web application.
• JDBC and EJB- to develop database applications 

In .NET we develop above applications using

• HTML- to develop web supportive application
• ASP.NET         - to develop web application.
• ADO.NET       - to develop database applications 

Web supportive application(HTML/APPLET) is used

•  for collecting input from end user by providing GUI then to pass it to web application
• for displaying output to end user by providing report                  

Web application (servlet and jsp technologies ) is used for

• Processing request and 
• Preparing response 

Server role is processing request means 

1. Reading input from network that is sent by end user via html forms, then
2. Executing business logic by using this input then
3. Finally generating output and sending it to JSP 

JSP role is preparing response means

• Generating dynamic HTML by using the output given by Servlet
• Sending the result HTML back to servlet

Then servlet sends this response to browser to display this output to end user.

1. Database Interaction Application (JDBC/EJB technologies) is used for performing CRUD operation on DB                                                                                                                               DB terminology                                                                                                                            C-       create (insert)R-        read(select)
   U-        update(update)
   D-        delete (deletes)