WCAT: A Tool to Test IIS Server and Client Capacity

The Microsoft Web Capacity Analysis Tool (WCAT) runs simulated workloads on client-server configurations. Using WCAT, you can test how your Internet Information Server and network configuration respond to a variety of different client requests for content, data, or Hypertext Markup Language (HTML) pages. The results of these tests can be used to determine the optimal server and network configuration for your computer running Microsoft Windows NT Server version 4.0 with Microsoft Internet Information Server (IIS) version 2.0 or 3.0. WCAT is specially designed to evaluate how Internet servers running Windows NT Server and Internet Information Server respond to various client workload simulations.

You can test different server and network configurations by using the prepared WCAT content and workload simulations. When you change your hardware and software configuration and repeat the prepared tests, you can identify how the new configuration affects server response to the simulated client workload. You can use WCAT to test servers with single or multiple processors and to test servers that are connected to multiple networks.

The Web Capacity Analysis Tool provides the following features:

• Prepared, ready-to-run workload simulations to test the most common aspects of server performance. These simulations provide World Wide Web content files of varying sizes to test your server’s response to different workloads.

• Prepared workload simulations to test the response of your server to Internet Server Application Programming Interface (ISAPI) extensions and Common Gateway Interface (CGI) applications. You can run these simulations even if your server does not currently run any ISAPI extensions or CGI applications.

• Prepared workload simulations to test the response of your server to Secure Sockets Layer (SSL) version 2.0 encryption.

• Prepared workload simulations to test the response of your Hypertext Transport Protocol (HTTP) service to HTTP keep-alives. HTTP keep-alives are an optimizing feature of servers and browsers; an HTTP keep-alive maintains a client connection after the initial request is satisfied. HTTP keep-alives are part of the HTTP version 1.1 specification.

• The ability to create and run your own client-server workload simulations.

• The ability to use cookies, a technology supported by some Web sites. Cookies are a means by which, under the HTTP protocol, a server or script can maintain state information on the client workstation. Cookies are usually used to provide Web site customization features.

• The ability to test servers connected to more than one network.