The best way to explain GSD-Proxy-Server configuration will be describing it with an example.
To have xMA-Web-Service web service and WebDAV web service running on one external port (provided in listener section) one has to add those two entries to services array in configuration file:
https://127.0.0.1 - WebDAV web service address
8888 - WebDAV web service port
https://127.0.0.1 - xMA-Web-Service web service address
8889 - xMA-Web-Service web service port
GSD-Proxy-Server allow to use HTTP, HTTPS and HTTP2 protocols. Each protocol should listen on different port. HTTP listener can redirect traffic to the services registered on HTTP protocol analogous situation works for HTTPS and HTTP2.