Often Web applications fail to meet their customers' needs and expectations. When a Web application generates errors, has poor response times, or is unavailable, customers can easily become frustrated. If your performance test procedure or methodology is not well thought out and properly planned, the odds of a successful Web application launch are significantly reduced. Microsoft has introduced Application Center Test (ACT) which ships along with Visual Studio .NET's Enterprise Developer and Architect editions which will help to stress test Web servers. It integrates with the Visual Studio .NET IDE.

Purpose of Application Center Test

Application Center Test (ACT) stress tests Web servers and analyze performance and scalability problems of Web applications.

ACT simulates a large group of users by opening multiple connections to the server and rapidly sending HTTP requests. It also supports several other authentication schemes and the SSL protocol, making it ideal for testing personalized and secure sites.

Application Center Test is compatible with all Web servers and Web applications that adhere to the HTTP protocol. ACT 's uses VBScript or Java Script macro recording feature and built-in graphing capability to record the tests and provide more clarity to the tester about the performance of the web site.

How to use ACT with Act.exe's browser recording feature:

I will take the example of testing a web page which will saves data to a database by calling a web service which in turn will call the Data access layer to save the data to the database.

1.Launch Act.exe from Programs | Microsoft Visual Studio .NET | Visual Studio .NET Enterprise Features | Microsoft Application Center Test to open the default ACT Samples project.

2. Right-click on the Tests node, select New Test to start the New Test Wizard, and click on Next to open the Test Source dialog.

3. Select the Record a New Test option, and click on Next twice to accept the VBScript language default, open the Browser Record dialog, and click on Start Recording to open an instance of IE.

4. Replace about: blank with your starting URL (eg: http://localhost/TestACT/AddTrain.aspx) in the Address textbox and record the sequence of operations to execute.

(In this example, the sequence of operations are -> enter the values in the controls on the web form (AddTrain.aspx) and will click on th e button which will call the web service to insert the value into the database. )

5. Return to the Wizard, click on Stop Recording, close IE, and click on Next.

6. In the Test Properties dialog, type the name of the test, click on Next and Finish to dismiss the Wizard, and click on the test name item under the Tests node to display the VBScript code automatically recorded for the test (see Figure 1).