0.3: What are application servers?
Application servers extend a Web server's capabilities to handle Web
application requests,
typically using Java technology. The application server makes it possible
for a server to generate a dynamic, customized response to a client request.
For example, suppose:
- A user at a Web browser on the public Internet visits a
company Web site. The user requests to use an application that
provides access to data in a database.
- The user request flows to the Web server.
- The Web server determines that the request involves an
application containing resources not handled directly by
the Web server (such as servlets). It forwards
the request to IBM WebSphere Application Server.
- The IBM WebSphere Application Server product forwards the request to
one of its application servers on which the application is running.
- The invoked application then processes the user request. For example:
- An application servlet prepares the user request
for processing by an enterprise bean that performs the database access.
- The application produces a dynamic Web page containing the results
of the user query.
- The application server collaborates with the Web server to return
the results to the user at the Web browser.