Hi Henning,

Very little is required for the proxy Badi, I would suggest you review the older post here:

https://archive.sap.com/discussions/thread/3309259

This will give some indication of what is required to be present in the Badi, however it maybe the case that you need to be more specific and for instance if you have different hosts or ports for different catalogs you can set this using the provided parameters for IV_WEBSERVICE_ID / CV_PROXY_HOST / CV_DEFAULT_HOST etc, this is especially important where loadbalancer or reverse proxy may change the host and/or port data on catalog return.

Regards,

Jason