Application Models

The .NET Framework Web classes can be accessed from a variety of application types, including console applications, ASP.NET, XML-based Web Services, Windows Forms, and Windows Services. However, it is important to realize that these application models can run under different environments. For example, a Windows Service or ASP.Net application can run under a different user account or impersonate different users, meaning it might not have the ability to change proxy settings or access to certain resources such as certificates.

The threading models also can vary from one application to another. For example, the ASP.NET environment uses a thread pool to satisfy incoming HTTP requests . This thread pool is also used by the HttpWebRequest class. This means that, if you are building a middle- tier application, you should be aware that both the Web server (ASP.NET) and any back-end Web requests issued will share the same limited set of threads and you should adjust the limits accordingly . This is a significant contrast to using HttpWebRequest from within a console-based application where all work is started from a main execution thread.