|Microsoft Internet Security and Acceleration Server 2000|
Web (ISAPI) filters detect and process HTTP events, and can extend the functionality of the Web proxy service. By using the Internet Server application programming interface (API), ISA supports the Web filter extensibility model, which lets third-party developers examine and change the HTTP request and response flow. ISA does not support ISAPI extensions.
For more information about ISA support of Web filters, see Developing Web (ISAPI) Filters for ISA.