HTTP provides several means to allow Web Servers to obtain information from the browser. The most familiar example is when a user enters data into a form on a Web page and the data is sent to the Web Server, which can access the value of each form field. This example illustrates sending form field parameters to the Web Server with a POST method. In general, a browser can send cookies, headers, query string parameters, and form field parameters to the Web Server. Web Servers can also respond to the browser with cookies and custom headers. The Web Engine HTTP TXN Business Service (BS) allows Siebel Business Applications to retrieve or set cookies, headers, and query string and form field parameters.

The Web Engine HTTP TXN Business Service can be invoked by scripts or by workflow. The inbound HTTP request to the Siebel Web Engine (SWE) is parsed and the BS returns property sets containing cookies, headers, or parameters. In addition, server variables, which are not a part of the HTTP request header, can also be retrieved. The BS can also set a custom cookie or header in the HTTP response header generated by the SWE. The BS gives complete control over the request header received and response header sent by the SWE.