Web Server with TREX Extension 
The Web server is responsible for the communication between Java applications and the TREX servers. The application sends requests to the Web server in XML format using HTTP/HTTPS. The Web server converts the requests to a TREX-internal format and then forwards them to the responsible TREX servers.
A TREX component that enhances the Web server with TREX-specific functions is installed on the Web server. Technically, this component is implemented as follows:
On Windows, as an ISAPI server extension for the Microsoft Internet Information Server
On UNIX, as a shared library for the Apache Web server