WebSphere Application Server - IBM Redbooks

Figure 2-6 shows the typical flow of a Model 1 application.
Browser
Figure 2-6 Model 1 architecture application flow
For small projects, prototyping, and to quickly get an application completed, the
Model 1 architecture is quite popular because of its ease of development.
However, more complex applications will need to follow a different approach.
That approach is described as Model 2 architecture.
2.3.2 Model 2 architecture
1
Request
Response
3
Application Server
2
JSP Database
The all servlet and all JSP approach both have inherent problems mixing the
business logic of servlets with presentation of HTML. These two approaches
cause applications to become difficult to maintain and less flexible. For these
reasons, Model 2 architecture was introduced. Model 2 is basically a
Model-View-Controller (MVC) architecture (see 2.3.3, “MVC architectural
pattern” on page 28) that separates the business logic and content presentation.
Model 2 applications are more flexible and easier to maintain and extend
because the business logic and the presentation are isolated from one another.
Chapter 2. Application design 27