HTTP Request Processing in IIS

IIS 7 and later have a similar HTTP request-processing flow as IIS 6.0. The diagrams in this section provide an overview of an HTTP request in process.

The following list describes the request-processing flow that is shown in Figure 1:

1.When a client browser initiates an HTTP request for a resource on the Web server, HTTP.sys intercepts the request.
2.HTTP.sys contacts WAS to obtain information from the configuration store.
3.WAS requests configuration information from the configuration store, applicationHost.config.
4.The WWW Service receives configuration information, such as application pool and site configuration.
5.The WWW Service uses the configuration information to configure HTTP.sys.
6.WAS starts a worker process for the application pool to which the request was made.
7.The worker process processes the request and returns a response to HTTP.sys.
8.The client receives a response.