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:

  1. 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.
  2. The user request flows to the Web server.
  3. 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.
  4. The IBM WebSphere Application Server product forwards the request to one of its application servers on which the application is running.
  5. The invoked application then processes the user request. For example:
  6. The application server collaborates with the Web server to return the results to the user at the Web browser.