When the page dispatcher receives a client request, it determines the page name by checking the PathInfo portion of the target URL's request message. If the PathInfo portion is not blank, the page dispatcher uses the ending word of PathInfo as the page name. If the PathInfo portion is blank, the page dispatcher tries to determine a default page name. 

If the page dispatcher's DefaultPage property contains a page name, the page dispatcher uses this name as the default page name. If the DefaultPage property is blank and the Web application module is a page module, the page dispatcher uses the name of the Web application module as the default page name. 

If the page name is not blank, the page dispatcher searches for a Web page module with a matching name. If it finds a Web page module, it calls that module to generate a response. If the page name is blank, or if the page dispatcher does not find a Web page module, the page dispatcher raises an exception. 

The following figure shows how the page dispatcher responds to a request.